Couple of thoughts on this:
- As a general rule, I have a deep/strong hatred for Web applications. They have their place in the IT world (much like rats have their place in the animal world...), but in general I think they are the WRONG tool for the job 90% of the time when it comes to corporate line of business (LOB) applciation development. I learned to develop writing green screen applications on UNIX - when I moved to VB2 development I felt like I could finally build a useful application that wasn't an insult to my users - when I wrote my first Web application I felt like I had taken a huge step back...reminded me a LOT of build green screen apps just with some new bells and whistles.
- AJAX has changed my opinion on that somewhat. I remember the first time I ran the Outlook Web Client for Exchange 2000 (the first AJAX app in my book...we just didn't have a cool name for it) ...my first thought was "this doesn't suck"...high priase for a Web application in my book. Google has done an amazing job of using this technology to change the way people think about Web apps.
- Google took it to another level in the past year. Between Gmail and Google Maps they have changed people’s expectations of what a Web User Experience should be like - it is possible for them not to suck. Put it another way, Web applciations are rapidly closing in on the level of user experience developers could deliver with VB3...also high praise in my book. Funny thing is that MS did it first with the Exchange web client, but because that is limited to corporate customers it didn’t have anywhere near the impact that something like Google Maps did.
- MAN the ASP.NET team has their stuff together. More so than any other MS team they have consistently delivered products that were rock solid, VERY well thought out, and leapfrogged the competition. Not surprising that they are adding support to this to the platform given their track record, but still great to see.
Bottom line - do I think AJAX (and the fact that ASP.NET will support it...) changes the decision matrix in terms of when to build a smart client and when to build a Web app for corporate LOB apps? Not really. I still contend that if you solve the deployment challange, 90+% of LOB apps will deliver a better/more efficient user experience via a smart client than a Web app. If ASP.NET allows me to build an AJAX app quickly and easily that percentage might drop to 80%, but no lower than that in my opinion.
That said, for the 10-20% of LOB apps and probably 75+% of external facing applications for which Web apps are the right way to go (you know...the 'rats'), I am really excited about how we can leverage the combination of AJAX technologies and the developer experience that the ASP.NET team delivers to make more and more Web apps not suck.