Got an email from Virtual Machine Program Manager

– AMD Virtualization (AMD-V) compatibility
– Intel Virtualization Technology (IVT) compatibility
– Volume Shadow Copy Service support
– Offline VHD mounting
– Active Directory integration using service connection points
– Host Clustering technical white paper

For complete details on the new features of Virtual Server R2 SP1 Beta2
and to download the software, please go to the Microsoft Connect Web
site (http://connect.microsoft.com/)
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Cheers,
Benjamin Armstrong

• Both the 32-bit version and 64-bit version of Virtual Server 2005 R2 SP1 Beta 2 are now available for download. 
  Note: A product key is not required for this release.
  
• Windows Vista will be supported as a guest OS when Virtual Server 2005 R2 SP1 becomes generally available. Virtual Machine Additions for a Vista Beta 2 Guest OS are available for download. If you are not running Windows Vista Beta 2 as a guest, you do not need this version of the Virtual Machine Additions.