Just got this from Canon: http://www.usa.canon.com/app/pdf/Win...patibility.pdf
At first glance all the Canon EOS models are listed as compatible, though several older models are shown with asterisks, which when one digs further is another way of saying "they're not compatible" in some way. Several surprises: 1Ds, for example, is only "compatible" through the use of a memory card reader.
Still, it's nice to get some solid info from Canon on this. They've been less than stellar in the past with keeping up with OS releases.
Edit: In my haste last night I mistakenly wrote "Microsoft Announces", instead of "Canon". I've just corrected that.