Hurray, Hyper-V is out. I'm going to be posting something on Hyper-V and Exchange 2007-SP1 pretty soon, however, in the meantime, it's out, go play with it NOW! BTW, this will not work with 2008 Beta, just in case you were wondering.

KB article 950050 is available here.

Grab the release notes here.

Download the x86  here and x64 here.