In case you missed it, you can now download the extensions to Visual Studio 2005 for developing WinFX projects (well, a beta version anyhow).
So, for example, once you've installed these and you start up VS2005 you'll see new project types for Avalon applications. Of course there's no visual design surface yet, so you'll have to build your apps using code rather than a visual designer but then that's all part of the fun, right? ;-)
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