Due to my new job, where I�m developing a web based ASP.Net WYSIWYG editor, I�ve been playing with several Ajax components available in the jungle out there.
Until now, I found two with merit, and I�ll be using both at same time because I found that they complete each other.
The point is that there are two major approaches to Ajax in the .Net world, the first is the invocation of methods on the server side, the other is a control based design approach where you just want your controls to work close to the usual ASP.net way.
Alexandre Gomes' Blog: 
