Windows 7 SDK is currently in Beta in connection with the recent Beta release of Windows 7. The SDK installation files are available via the Beta program portal on Connect as well as on the Microsoft Download Center.
This Beta SDK release includes:
Documentation, a new Windows 7 Developer Guide and Quality cookbook.
Samples, including nearly 250 samples added and refreshed specifically for the Beta.
Headers/libraries, over 100 new headers and libraries added to the SDK.
Tools, seven new tools added to SDK during Beta.
The Windows 7 SDK headers, libs, and tools that can integrate with Visual Studio 2008 when both the SDK and Visual Studio 2008 are installed.
Visual Studio 2008 SP1 C++ command line compiler toolset and matching CRT.
Please read the "what's new" section of the SDK documentation for a complete listing of contents and additions.