LOL wow at the people that think this is impossible :-S
MS expect to ship 5 million over the next 8 weeks alone ...
they'll do that again next christmas with it's inevitable price cut ($99/£99 making it much more attractive)
Say it only manages 3 mill next Jan-Oct .. (again very low estimate ...) we're already up to 13 million by end of 2011.
and 20 mill is virtually impossible how?