Here's a dirty secret. ready?
Microsoft has MORE than enough units manufactured to meet the demand. But they _purposely_ restrict supply at the beginning, just to build a euphoria, force people to line up at 12am and create lovely news stories about the "big demand sold-out status" of xbox units.
Great advertising and makes it seem so sought after and desirable.
A few weeks later -- once the euphoria has died down -- and the mom/daddy shoppers start buying gifts for xmas -- a shitload of xbox 360's will be released to meet the demand. Microsoft knows that if you don't meet the demand -- that's lost profits. No one wants to buy xbox 360's on jan 2nd so shipping them out then will be kinda pointless.
I'll just wait 3 weeks then drive up to walmart and buy one off the shelf. la dee da.