It's awesome that Virtual PC Images for Visual Studio 2008 Beta are made available. When I played with the Visual Studio 2005 Beta, I installed directly on my main development machine and it left some unwanted artifacts which later caused problems.
But here is something that has bit me a couple of times when using the VS2008 VPC's for Silverlight Development. If you happen to find that you can't bring up any Silverlight applications in the Internet Zone, keep in mind that there are some things disabled under Windows Server 2003 for security reasons that you must re-enable.
Here is what you need to tweak:
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