Hey... I've done it a few times now..
The first time, I choose to install it to a separate partition.. and thus dual boot Vista & Windows 7... this was painless and required nothing other than already having the D:\ partition setup. The clean install setup took about
35 minutes and I had no problems.
The 2nd time, I choose to "upgrade" that Win 7 installation using my post above that changes the "cversion.ini" so that the installer will upgrade the "Beta" to the "RC"... this also was painless, aside from having to make that minor file change... but the upgrade took
a little over an hour. If I would do it again, I would skip the upgrade and just format my D:\ and start fresh. I have not tried to "upgrade" a Windows Vista partition to straight Win 7.. while this WILL be possible with the RTM of Win 7, I dont know off hand if it can be done with the RC. I am guessing that it can with a simple modification of the "cversion.ini" to include a minor= build of 6000 (Vista).
But keep in mind that the RC will expire sometime next year, so I would advise you to first install it as a dual-boot machine, in case you want to fall back to Vista.. (or i guess WinXP)..
Any other specific questions.. I'd be happy to answer..
thanks!