From what I've read, Windows 7 is basically meant to replace Vista completely. They probably want to get as much of Vista gone as possible. In the process, they want to make XP disappear as well since it's been available for nearly a decade now, so the 32 bit version is to get the XP folks to upgrade as I'm guessing that most XP folks don't have hardware that could support 64 bit. I'd say that most systems still around that have XP on them should be able to run W7 fairly well. I have it installed on an old Dell laptop that has 512MB of RAM and it works fine, and the dedicated graphics allow for transparency even. The other thing to think about is that MS is marketing heavily in the netbook segment as well, and I don't think that the Intel Atom processors that are in most of them are capable of 64bit instructions yet, but I could be wrong. It actually wouldn't surprise me if they fork at some point and start developing a different OS just for netbooks at some point, depending on how hardware advances in that segment compared to the deskop and full size laptop arena over the next couple of years.