Now I know what you're thinking -- "how?" The answer is actually quite simple: the Wii is not nearly as strong as some want to believe and Sony's strong growth is the result of a lower hardware price, which is allowing it to catch up to the pack.
XBOX will win because I want. Greatest argument ever
Sony has sold roughly 13 million Playstation 3 units worldwide, while Nintendo has sold 25 million Wiis and Microsoft has sold 19 million Xbox 360s. And while Sony won't cite those figures, it chooses instead to mention "velocity" -- the rate at which its sales are increasing.
and nothing about being released one year later (one and a half in europe)