Ok, I have Vista Ultimate, which has no restrictions on being used as a VM. I installed it with Boot Camp, by extracting the XP drivers and installing them individually. I seem to have a stable, fast Vista Ultimate Boot Camp partition. I have been unable to set up Parallels RC 3120 or 3150 to recognize it. When running through the initial set up, I get to the screen where I should be able to choose the Boot Camp partition, but it's grayed out. (image borrowed from a post in another thread by chreriksen) Has anyone succeeded at this yet? I know its a beta, but I'm eager.
You can not run a VM based upon a Vista bootcamp partition. Only XP bootcamp partitions work at present.