Bertrand recently published our roadmap for ASP.NET Ajax. 

Our goal is to describe some of the proposed features that we are considering investing in future releases of ASP.NET AJAX, Visual Web Developer, and the ASP.NET AJAX Control Toolkit.  
We really appreciate your feedback, so this document is intended as much for you to provide an input to our direction as well as to give some indication of what the teams are investing in.

We'd love to hear your thoughts!