Durnurd's right, it's not on the list for backwards compatibility.
Durnurd is wrong, however, because the shortage is being fixed this month, and all the bugs are being worked out with these new ones coming into stores. So uhhhh.... yeah, you should get one.
Oh, and yes, the new technology will be 'outdated' (you know how technology goes) in a few years, so they'll drop the price of that thing. Go for 360 and enjoy gaming until that thing comes out ---or until that darn Revolution comes out. Damnit, I can't wait for that too.