I don't think it ever will. In America the gap is not only sizable, but growing. In Europe they are neck and neck, and in Japan PS3 sales have been sluggish, 360 in Japan is....Also the 360 is a moving target and every week, month, and year that it outsells the PS3 or even in the case of ps3 outselling the 360 the amount is not sizeable enough to really cut deeply into its' lead.
Bet between Slimbeast and Arius Dion about Wii sales 2009:
If the Wii sells less than 20 million in 2009 (as defined by VGC sales between week ending 3d Jan 2009 to week ending 4th Jan 2010) Slimebeast wins and get to control Arius Dion's sig for 1 month.
If the Wii sells more than 20 million in 2009 (as defined above) Arius Dion wins and gets to control Slimebeast's sig for 1 month.
