I've recently purchased a new media PC to run Windows 7 RC with the new and refreshed WMC compared to Vista. Problem is that the everything works fine until the computer restarts and does the "Completing installation" in which it hangs for an extreme amount of time of where the bar appears to be at around 75%. However, that happens after it seems to refresh the resolution. I let it sit there for an hour or so to see the "Setting up Windows" portion occur with the line of light with the blip in the center in which it proceeded to hang again for another hour or so until I could enter my information.
I actually got it to boot Windows 7 but it crashed to a black screen with a flashing underscore symbol. Once that happened I tried Vista and got everything installed and updated and when I went to restart it after the update it hung up after entering my password.