Today Google put the GWT (Google Web Toolkit [1]) online which includes several UI controls, but also the possibility to exchange data between server and client and back. While downloading the framework and watching the examples I found following page: Sharing objects between Java source and JavaScript [2]. Hm, if I compare the data types that are supported with Ajax.NET Professional [3] I feel happy. Since I added more .NET 2.0 support like generic Dictionary or Nullable types... I can use any code that I'm currently using, great. In the last weeks I removed a lot of old common ASP.NET postbacks to AJAX requests. Most features could easily replaced by adding only the AjaxMethod attribute, no other C# code had to be changed. On the client-side, of course, I had to write some JavaScript, but this you have to do everytime you are talking about Web 2.0 or AJAX.
Maybe I should do some Web 2.0 development to add UI controls and effects to my library. Currently I'm still concentrated on doing the AJAX stuff. I will do some more tests with Web 2.0 frameworks like the Yahoo or Google framework. Yahoo has done a lot of great work on controls, and as I can see it should be very easy to use Ajax.NET Professional with the Yahoo UI controls. I will put some examples online the next days, hopefully.