Try this:
http://longhorn.msdn.microsoft.com/lhsdk/ndp/ovrwhatsnewinwhidbeyalpha.aspx.

Hi,

Thanks for posting in the community!
I'm not able to find an update list for Whidbey.
Whidbey is still under developing, the namespaces and classes is not
finally freezed. So probably the Doc team haven't complete such
documentation at this time. If you would like to have an update list when
the whidbey releases, you may send a feedback to the MSDN feedback alias to
let them know. For now, you may try reading some techinical articles for
whidbey and browsing some MSFT blogs to learn more feature about it. Here
is a resource page contains much links about Whidbey:
http://www.mscorlib.com/DesktopDefault.aspx?tabid=263

Hope it helps!

Best regards,

Ying-Shen Yu [MSFT]
Microsoft community Support
Get Secure! - www.microsoft.com/security

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