I'm getting the same problem too. I'm in Canada, and also have XP-64. I'm assuming this is another microsoft avoiding XP-64 in light of Vista situation.

I recently made a Games for Windows Live account so I could play Dawn of War 2. I eventually will hook this account up to my 360 (which I assume will be a whole other problem, but..) and noticed it automatically set my region to United States. I live in Canada, so it's my impression that if I was ever to buy points, or buy Live Arcade games, they