Microsoft Web UI

Microsoft has so many web technologies to do the same Web UI AJAX thingy. It does not even funny. Here is the (not exhaustive) list :

• ASP.NET/AJAX
• SliverLight
• Volta
  
• ASP.NET/MVC (a programming model that not related to always related AJAX)
• Visual Web GUI
• ...

Sometimes it is a tough decision to make, especially they are still new and you have to overcome some quirks that are not very well-documented. I used the ASP.NET/AJAX in my most recent project. It turned out that in order to write a AJAX control extender you have to learn a whole framework/library in a completely different language (JavaScript). What a nightmare to maintain the code.