For users who want to move virtual machines from Virtual Server to Hyper-V there are two resources you should be aware of.
The first is the Virtual Server to Hyper-V Migration Guide that is now available here: http://technet.microsoft.com/en-us/library/dd296684.aspx. This explains the process for moving a virtual machine from Virtual server to Hyper-V and outlines all the catches and steps involved. The second is the VMC to Hyper-V Import tool that has been developed by Matthijs and can be downloaded here: http://blogs.technet.com/matthts/archive/2008/09/12/vmc-to-hyper-v-import-tool-available.aspx. This tool takes VMC files and creates Hyper-V virtual machines with the same configuration.