I can't see the PS3 ever passing the 360 in this region. The 360's lead over the PS3 is gigantic in America; in fact, the 360 has a bigger lead (6.5m) than the PS3 has total consoles sold (5.8m)! In order to predict the PS3 passing it, we'd have to see a consistent pattern of PS3 sales outpacing 360 sales for months and years on end, which hasn't shown up at all.
Another way to look at it is thusly: if the 360 stopped selling today, it would still take more than 2 years for the PS3 to pass it in American sales.
So it's not inconceivable, but it would require Microsoft taking the 360 off the market years and years ahead of the PS3, which is rather unlikely. Once the next group of consoles come out, sales for both PS360 will die off, as all the tech savants rush to get the latest and greatest device. I'd be shocked if this race ever gets within 5m.
End of 2008 totals: Wii 42m, 360 24m, PS3 18.5m (made Jan. 4, 2008)
