I believe that it would, i can confirm this, is the data from a windows 7 install or another operating system. I know when i switched from windows 7 rc to, professional, that i partitioned my single hard drive, put a backup on the one partition, then installed windows 7 on the other, and the backup was maintained
That was something I found kinda annoying. Why not make the RC upgradeable to anything? I know it was an ultimate, but that doesn't make it any less annoying. Especially when my install was only a few months old at that point.