Microsoft Windows SDK Beta for Windows 7 and .NET Framework 3.5 SP1

The Windows SDK for Windows 7 and .NET Framework 3.5 SP1: BETA provides the documentation, samples, header files, libraries, and tools (including C++ compilers) that you need to develop applications to run on Windows 7 BETA and the .NET Framework 3.5 SP1.

More info and download: Microsoft Windows SDK Beta for Windows 7 and .NET Framework 3.5 SP1