Allready saw some XNA stuff on the devdays2006, dont know how mature its gonna be, but I guess its fun to play with at the end of the month.

From the site:
Check out the latest news on the new XNA Framework and XNA Game Studio Express. XNA Game Studio Express is a set of tools based on Visual C# Express 2005 that allow students and hobbyists to build games that target both Windows and Xbox 360. The XNA Framework is a set of managed libraries, based on the .NET 2.0 Framework, tuned for game development.
read more:
http://msdn.microsoft.com/directx/XNA/