Few assumptions are safe in the IT industry. A few years back, it was obvious that that PCs running Windows were beating the Apple Mac into a tiny niche. Things look different now. If you planned your IT strategy on the earlier assumption and have not changed, you are now getting it wrong.

Another not entirely unrelated area is the significance of the mobile web. Mobile phones have had web browsers for as long as anyone can remember; but for most of that time actually using them has been frustrating and slow. Remember trying to scroll a tiny window around some web page broken by non-functioning Javascript or CSS, looking for a critical piece of information such as an address or schedule?

In consequence, the extent of mobile browsing was small and mainly focused on niche areas like travel.

It all changed with the iPhone. Those contracts are expensive, but once you buy in you generally get an unlimited data connection, and more important, a decent browser which is a version of Safari, built with WebKit. That same engine is now used in many other devices, not least those running Google Android. Suddenly, users do want to use their mobiles to browse the web; and they will be hitting your web site or application and trying to use it.

Check your stats. I run another blog at itwriting.com, and when a reader complained about its appearance on a mobile, I added a wordpress plugin which both fixes the layout and reports the traffic. According to the plugin, 5% of the traffic was from mobile users. Once the site was fixed, the figure grew dramatically, to over 15%.

A tech news blog is just the sort of thing that appeals to mobile users, so those figures will not apply in every case. The point though is this: all those assumptions about limited mobile usage which once seemed safe now no longer apply.

Here's another line I often hear. There's no need to optimise your site for mobile, since the more advanced mobile browsers work fine with normal web sites.

Unfortunately that is not the case. They work much better than older ones, true. However, the displays are very much smaller and the connection speed often much slower than on the desktop. If you want your site to be a pleasant experience for mobile users, you will likely have to deliver customised content for them.

Does everyone get this anyway? If you have a few spare minutes, head over to mobiReady and try out a few sites; or download the Android emulator; or of course use a real device to test sites that you are involved in or interested in. I did so before writing this piece, discovering that the web still looks very broken once you go beyond the top sites.

The positive spin on this is that optimising for mobile can be a relatively easy way to gain commercial advantage.

Talking of safe assumptions, one that seems good right now is that the number of web-connected mobile devices is going to grow rapidly in the coming years. Optimising for mobile was always the right thing to do. Now it is essential.

At the Future of Web Applications conference earlier this month I spoke to Microsoft's corporate VP of the .NET Developer Platform, Scott Guthrie about ASP.NET MVC. Guthrie is a co-inventor of ASP.NET along with Mark Anders, now at Adobe. A few months back I wrote a piece entitled ASP.NET MVC rescues Microsoft's web platform, but I wanted to hear from Guthrie how he sees the framework evolving, and to explore whether it is time to abandon the older Web Forms approach. How does he see the future of the platform?

"The amount of buzz and religious fanaticism about [ASP.NET MVC] is amongst the highest I've been involved in, certainly since .NET 1.0 and Silverlight. Some people prefer the Web Forms model  and I emphasise that Web Forms is not going away, there's all the new stuff that's coming for Web Forms 4.0.

"MVC is an alternative way to do UI and still leverage ASP.NET. For crowds like the one here at FOWA that wants total control over the markup, and who like test-driven development, it's a dream framework. Those folk tend to be more online, so they communicate better which is part of the reason you hear the buzz. I think we'll have more than a million developers using ASP.NET MVC within the first twelve months."

In your talk you mentioned the stackoverflow site which performs very well but runs on not very much in terms of hardware? Is ASP.NET MVC more efficient than Web Forms?

"ASP.NET itself has always been really fast, we've had a lot of success with large sites. One of the things people like about ASP.NET MVC is that the model fits to what they are expecting, for the large LAMP contingent which is heavily represented at this conference.  And when they do the performance testing they say 'Holy cow, this thing is fast.'  Stackoverflow is a great example, written I think within three weeks and scaling to that level with two machines. Performance is a feature, and one of the reasons StackOverflow works as well as it does is that it's instantaneous response time.

"Conchango just did a site, implemented in 20 weeks, a giant ecommerce project, it's 100% ASP.NET MVC. The SEO is phenomenal, the YSlow rating is phenomenal, they're just blown away. It was fun talking to them last night - the guy was jokingly saying, 'I can't believe it works so well'. It's like the best marketing literature in the world times ten. More and more when I give talks I'd say half the people are new to ASP.NET MVC, and the other half come upand say, 'by the way we've done five sites on it.' That's great to hear."

On equivalent hardware and leaving aside different coding styles, is ASP.NET MVC going to scale that bit better than Web Forms?

"No. The reality is you can build hugely scalable sites with each. Where it does help a little bit is that there is smaller page size and there's a bit more control. There's less abstractions."

And the page lifecycle is shorter?

"It is shorter. I don't think that's making any measurable perf difference. It's more that it naturally flows to what they're doing. I do think it's fast, in the same way that web forms can be fast too. But it promotes a certain way of working that, if you know what you're doing, you tend to build really fast apps."

What about the open source aspect? Are people contributing code?

"People are not contributing code directly to ASP.NET MVC, but we're shippling JQuery and we're shipping JQuery validation which are open source projects, and we are integrating them into our code. With JQuery in ASP.NET MVC version 1.0 we just shippped it, whereas in version 2.0 we have helper libraries that are making big usage of it.

"I'd say that's a first for Microsoft, we're actually taking open source software that has multiple contributors, and using it in a deep way within our own product.

"We ship the ASP.NET MVC source code under an OSI Licence. You can take the code, you can modify it, you can do builds. I know a few people that have done customer tweaks, but for the most part it's that people like being able to learn the product through the code. There's also the reassurance of knowing that if they ran into something, they could fix it."

Would you consider accepting community contributions to the code?

"We've thought about it. I think a lot of people interpret open source as 'hey, anyone can just submit stuff'. The reality is that pretty much every open source project has a closed set of contributors. They come from multiple organisations or backgrounds, but you don't check anything into the Linux kernel without Linus or Andrew signing off on the fix. That would be true of ASP.NET MVC, in that there would be a core set of contributors. At some point I think we will probably open it up to let people to contribute code, or at least patches."

What's new in the latest ASP.NET MVC 2.0 preview?

"The ability to easily do forms validation for input, server-side and especially client-side in a very declarative, easy way, is a huge productivity win.

"'Areas' provide a way to take a large project and easily structure it into multiple small projects.

"New form helpers and what we call editor and display templates for customising them  is an innovative way to get strong typing, intellisense and debugging support, and a lot of flexibility in terms of UI generation.

"Asynchronous controllers allow you to call call services on the web, the Twitter, the Facebooks of the world, and  much more efficiently  scale your web server. The classic problem if you're calling Twitter is what's the response time of Twitter? What's the response time of Facebook? Most web servers are multi-threaded so they're processing multiple requests, but say they have 10 threads running and 15 requests come in, and each of those requests need to go and access Twitter, you're going to block 5 people while nothing is going on on the server. With the Async support we provide a way that you within your app can say, I'm going to wait for a while, yield back the thread, and when the data comes back reschedule me. It can dramatically improve the scalability of the site.

"We're doing a bunch of work around helpers for caching, paging, and a other things. In general it's a compatible release, we're trying to listen to the community, keep it a very transparent, Agile-based development process and knock off the top asks.

"We ship the source to every preview, take lots of feedback. That's the other thing people have really liked about the project, this open feedback. They don't feel like we're telling them, here's the way it is, take it or leave it. They like the fact that we've been iterating with them."

Guthrie is diplomatic about the question of Web Forms versus ASP.NET MVC, and even though I pressed him, would not quite agree that it performs much better. Clearly Web Forms is not going away. Take a look though at some of the comments from practitioners like Howard van Rooijen of EMC (formerly Conchango):

One of the great aspects of ASP.NET MVC is how lean and clean the architecture is - there is so little background noise compared to WebForms; possibly the best illustration of this is the difference between the MVC Request Pipeline vs. WebForm Page Lifecycle. The number of hoops you are forced to jump through in WebForms, compared to MVC is quite staggering.

Overall I heard nothing to change my general opinion, that if you can use ASP.NET MVC rather than Web Forms, you probably should.

Too strong? Maybe, but the ASP.NET Web Forms programming model has run its course. It was hugely impressive when it originally appeared - I remember it being announced as ASP+ in 2000, and how phenomenal it seemed. You can build a web page visually, using a rich set of controls, and have ASP.NET abstract away much of the problem of managing state. It also lets you write code in any .NET language, which is just-in-time compiled at runtime for fast performance.

ASP.NET works the same as ever today; but the web has moved on. The Web Forms model makes programming the web more like programming Windows, which was cool at the time but not any longer.

Fortunately for Microsoft, it has an alternative, called ASP.NET MVC. The first full release was announced at the Mix09 conference last week, and you can download it now. I took the opportunity to ask some of the delegates what they thought of it.

The reactions I got fell into two broad categories. The first group found it difficult to puzzle out what it really was, even those who had attended sessions on the subject. The second group loved it, and never ever wanted to go near Web Forms again. In fact, such was the frustration with Web Forms among some developers, that they had developed their own alternative frameworks but were now moving to the official one.

So what's wrong with Web Forms? Complaints I heard include that it is not testable; that it is not really compatible with AJAX; that it is inflexible; that ViewState, hidden form data which preserves state across page refreshes, is a nuisance; and that it is hard to write REST-style applications or those which properly support the Back button.

Enter ASP.NET MVC, which answers all of these complaints. MVC stands for Model View Controller, though having played with it a little I find the name somewhat misleading, as well as being a mouthful (contrast the delightfully-named MonoRail, which is an interesting alternative). Why misleading? Well, it doesn't have much of a Model, as this post observes. It does have views and controllers; but I think one of the reasons developers find it hard to grok is that starting with a discussion about MVC architecture is not the best way to teach it.

I think the place to start is with URLs and routing. It also helps to know that ASP.NET MVC follows the principle of convention over configuration (though not to the same extent as Ruby on Rails). In a nutshell, ASP.NET MVC breaks the link between the URL in the browser and aspx files on the web server; instead, it processes the URL and returns what you want it to return.

A "View" in ASP.NET MVC is an .aspx page, but in the form of a lightweight template, not a Web Forms with a complex page lifecycle.

I've been playing with ASP.NET MVC recently, and it is a delight. Yes, there is more manual coding than with Web Forms, but it is worth it for the additional control you gain. Even the performance seems better, a consequence of the lightweight approach. As it happens, I'm also a believer in test-driven development. I guess I'm in the second group that I spoke to at Mix09.

Microsoft is not killing off Web Forms; rather, it is very insistent that they remain under full development. I get the impression that the company expects ASP.NET MVC to be a minority choice.

Nevertheless, if you work with ASP.NET do not hesitate to check out the new framework. Personally I think ASP.NET MVC might just rescue its web platform from a slow but inevitable decline.

Historically, the web development choice between the Microsoft platform and open source has been a fork in the road with many consequences. Choose Microsoft, and you generally use Visual Studio, Internet Information Server, ASP.NET, C# or Visual Basic, and SQL Server for the database manager. Choose open source, and you most likely target LAMP in one of its guises, the most common being Linux, Apache, MySQL and PHP, and work in Eclipse or almost anything other than Visual Studio.

Recently the boundaries have been blurring a little. Apache actually runs nicely on Windows, and I've used it happily to host a Subversion repository, while on the other side Microsoft has been making an effort to support PHP in IIS 7.0. But what about running ASP.NET on Linux, is that a silly idea?

I've been following the efforts of the Mono project in this area for some time, though it's been a while since I've tried it out. Mono was originally focused more on desktop than web applications, and I've used it mostly in that context. When laterooms.com tried Mono in early 2006 it quickly gave up, citing problems with Mono's Boehm garbage collector; see the developer's comments to my blog post at the time.

Still, that was three years ago. I had another look a couple of weeks ago, and I've been impressed. In particular, the ability to develop in Visual Studio and deploy to Linux is interesting. I'm working on a small project, and getting this working is remarkably simple. I used Visual Studio 2008, but set the project to target .NET Framework 2.0, as Mono lags behind Microsoft in implementing the latest .NET APIs, and using MySQL rather than SQL Server, since this is available on my Linux web server. Using MySQL with .NET is straightforward thanks to the official ADO.Net provider, which specifically supports Mono as well as Microsoft .NET.

On the web server, running Debian 5.0 Linux (Lenny), I installed the libapache2-mod-mono and mono-apache-server2 packages using Aptitude. Next, I configured Apache to use Mono on a particular web site, with a few lines of manual configuration, as explained here, and imported the MySQL database from the Windows development machine to the Linux web server.

Back in Visual Studio, I compiled the web site, uploaded it, and it worked first try. Performance is good as well.

I realise that a number of caveats apply. It's worth reading this page, the current Mono todo list, which notes some of the important areas where Mono is lacking and includes the comment:

Mono is known to be not as performant as the .NET Framework.

Note that Mono still uses the Boehm garbage collector, though an alternative is in development. Further, Mono does not implement the entire .NET Framework. Mono is a brave choice; Windows and IIS the sensible option for .NET applications.

It still seems to me significant that you can easily deploy to Linux and Apache using Mono. Not all applications are mission-critical, and not all applications need to scale as well as Laterooms.com. Mono has a number of attractions. First, it is open source, so in the event of problems you can always obtain and amend the source code. Second, running on Apache and Linux is a considerable saving in license costs. Third, you can get official developer support from Novell.

Why would you use C# and ASP.NET rather than PHP or Java? The main reason would be because you know and like the language, the platform, and/or the Visual Studio IDE. In an interesting report on the state of the computer book market, O'Reilly notes that C# is now the largest programming language for all book sales. Thanks to Mono, you can use C# but still deploy to an open source platform.

It also seems to me that Microsoft's official support for Moonlight, the Mono implementation of Silverlight, is important. Microsoft now needs Mono, in order to tick the cross-platform box and compete with Flash, giving more assurance to its long-term future.

Mono's growth over nearly a decade has been slow but steady. Perhaps now is the moment that it creeps into the mainstream.

Are you using Mono, for web or desktop development? I'd be interested in your comments.

Adobe's MAX conference in San Francisco this week was focused on what it calls the "Flash Platform", a technology stack oriented round the Flash multimedia runtime. The "platform" word highlights the fact that you can code for Flash and have your application run everywhere that Flash runs, including Windows, Mac, Linux, and some mobile devices as long as they are not from Apple. It is not a complete platform, being essentially an Internet client, though there are some server-side pieces such as LiveCycle Data Services, to simplify and optimize communication between Flash clients and Java middleware. You can also blur the distinction between browser and desktop with AIR, which runs Flash outside the browser and adds a local database engine.

So what's new? There was the usual set of announcements. The key ones are as follows:

AIR 1.5: an update to the desktop runtime which adds support for Flash Player 10 features such as Pixel Bender, for runtime graphical effects, and an option to encrypt local databases. There is also the SquirrelFish JavaScript interpreter - though this only comes into play if you are running JavaScript within HTML, rendered by WebKit, rather than ActionScript without the Flash runtime, which has its own just-in-time compiler. AIR 1.5 is available now.

A new version of Flex and the Eclipse-based Flex Builder IDE, code-named Gumbo. This has a new skinning and component architecture, more advanced text rendering, easier two-way data binding and a new Client Data Management (CDM) feature which from early descriptions looks reminiscent of a .NET dataset. You work with data on the client, storing updates locally, then zap the updates back across the wire in a single update operation. One thing that is not yet clear to me is the extent to which CDM requires LiveCycle on the server; I'll be sure to clarify this in a couple of weeks at MAX Europe (I was not present at the US event). The database aspect is significant, because so many enterprise applications boil down to CRUD (Create, Retrieve, Update, Delete) in one form or another.

Catalyst, formerly code-named Thermo, was previewed. This is a fascinating product which converts Photoshop artwork into Flex code; it also allows designers to create and preview a degree of interaction in their designs. Catalyst shares the same project format as Flex Builder. Again, I will be taking a closer look at MAX Europe. Here's a preview screen grab:

Cocomo (yet another codename) is a cloud effort from Adobe, focused on conferencing. Adobe hosts the services and provides Flex components to enable file sharing, text and VOIP (Voice over IP) chat, whiteboards, and data messaging; there is also user management built in.

Alchemy is a tool that converts C/C++ code to ActionScript, for execution within the Flash player. It's intended for re-use of existing libraries, not for general development.

Third-party announcements that caught my eye included Ensemble's Flex add-in for Visual Studio (though I was underwhelmed by the preview), and Zend's addition of AMF (Action Message Format) into its PHP Framework. AMF is a binary format that optimizes data transfer between servers and Flash clients.

Although none of these announcements is spectacular in itself, taken together they show the momentum behind Flash as a client for applications as well as video and multimedia, as I have mentioned here before. A good thing? Designers love Flash because of the freedom it gives them, along with the excellence of Adobe's design tools - Creative Suite 4 really is spectacular. Nevertheless, I have a nagging concern that if we adopt Flash rather than AJAX - interactivity in HTML and Javascript - for our next-generation clients, we are giving away the openness of the Web, because Flash is proprietary technology. I recommend this thoughtful post from Google's Brad Neuberg, which recommends not only open-sourcing the Flash runtime, but also integrating it more deeply with the browser and embracing web standards. There's little chance of Adobe adopting Neuberg's proposals, but he does a good job of spelling out the issues. Flash is compelling, as is Microsoft's Silverlight, but each is controlled by a single vendor. Do you think that matters? I'd be interested to hear your opinions.