I'm often getting asked for paritcular fixes required for Hyper-V . There is a comprehensive list published here:

http://technet.microsoft.com/en-us/library/dd430893.aspx

Note the links for other products like SCVMM and DPM.

 

Here is the list for Windows Server 2008 R2

http://technet.microsoft.com/en-us/library/ff394763(WS.10).aspx

Cheers

Robert