There is no mention of Windows 7 on the BMD website to the best of my knowledge. You might get it to work. You might not. They will certainly not support anything not in the tech spec for the products which leaves VistaSP1 64bit as the latest OS for windows – something I’ve avoided myself.
I only add to this post because, like you I think, I now feel I need to move up to 64bit, in my case with Premiere Pro CS4. PPro simply isn’t workable on 32bit with the kind of multilayer long form time lines that I work on using Boris BCC and Graffiti. It regularly stalls at 1400Mb RAM leaving me with lost time and endless repetition of work. Considering that W7 is launched this week and that the code has been out for ages in the community I’m a pit perturbed that BMD haven’t at least mentioned it as on the agenda.