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I wrote a Parallels blog post for Windows 7 RC running within Parallels Desktop 4.0 for Mac. You can find it HERE.

Overall, not too shabby. I really like how smooth it runs, and installation was quick as well. There are a couple screenshots posted there also, if you're interested in seeing it.
 
I run Windows 7 RC in VMware Fusion 2.0.4 and it runs very smoothly. Much better experience than (the dreaded) Vista which I ran for about 32 minutes in a VM. Almost ready to give up my Windows XP VM for work.... Almost... :)
 
It's running fine for me in VMware Fusion. Overall it runs fairly well, with no slowdowns or hiccups. Speed-wise it feels about the same as my Windows XP VM, and faster than any Vista VM I have ever used. There are no question marks in device manager; all hardware was recognized and drivers provided through VMware Tools, although I haven't tested everything to see what actually works and what does not.
 
The only thing I've found that doesn't work in Fusion (other than Aero, which I expected) is the Windows Media Center. It claims the video driver isn't able to support it, so it doesn't play any of the sample video.
 
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