Virtual Server 2005 Performance
For those people trying out Virtual Server, like me, you can get a significant performance gain by using Remote Desktop Connection to get to your guest operating systems, rather than the web client, which for me at least (3.2ghz, 1.5gbram, 7200rpm hd) performs like a dog.
It also has the added benefit of letting you run two virtual machines on two separate monitors in fullscreen, which is a big plus.