You can now download Virtual Server 2005 R2 SP1 BETA2 from http://connect.microsoft.com. As with other beta software, you need to register for the beta first.

This release is pretty significant because it is the first version to support both AMD-V and Intel-VT hardware virtualization. From the release notes, it includes:

• 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

The best part is that you can upgrade existing installations very easily:

I just upgraded my 32–bit workstation, and everything is working like a charm.