The great news for who is mainly a windows client developer (like the author of this blog 
) is that with the .NET Framework 3.5 SP1 (actually in Beta 1 stage) will be released the .NET Framework 3.5 SP1 Client Profile, a subset of the .NET 3.5 library only for the client applications.
The new light "client .NET package" (about 26 Mb) will include these components:
- CLR
- WinForms
- ClickOnce
- WPF e WCF
and it will have a direct support inside Visual Studio 2008:
This helps to have a light installer when you deploy your applications.