Got one yesterday from the Gamestop in the Columbia, MD mall. I never owned a PS2 (though I have lived with a couple PS2 owners), so I figured this was the best time to pull the trigger since Sony didn't announce another backwards-compatible model.
I made the mistake of waiting until after work to jump on this deal... all of the mgs4 ps3 bundles are at least $650 before discount. I can't really afford that much up front, even if it comes to $420 in 60 days. Lame!
FWIW, I didn't have any problems making a Live Cashback account by going straight to search.live.com/cashback. It might have helped that I already had a Passport login.
This is an amazing deal. I could get a MGS4 80GB bundle for about $360 after cash back! Too bad I still have to pay the full price up front. That's the only thing holding me back right now... :(