There is a new Ajax toolkit in town with support for .Net and Dojo - pure C#. It looks promising so far but I wouldn't use it in any production environment as of yet as I have already experienced some bugs - its still in v0.1, you shouldn't be expecting a complete wrap but try it out. http://www.emergetk.com/emergetk

The Emerge Toolkit Has Arrived.

• Instantaneous, two way communication between server and browser.
• 100% C# 2.0. Write your entire application in your favorite CLR-supported language.
• Build application logic with existing widgets, or roll your own.
• Construct your interfaces in C# or XML. Control your design with CSS.
• Model your application domain with the integrated O/R mapper. Write your models in C# or XML. Store them in an embedded SQLite database, or soon MySQL or SQL Server!
• Prototype applications rapidly with our Scaffold and other data bound widgets
• Present data visually with rich, interactive SVG widgets.
• Tie everything together with our live data binding services -- makes simultaneous event updates a snap, perfect for the Living Web.
• GPL and commercial licenses available.