i xbox 360 has been out for almost double the time...so of course it sold double the consoles...
Predicted end of gen Results
PS3--------58,000,000 Ps3 takes the lead it late 2009 and never loses the lead again
Wii---------43,000,000 Wii fade starts to die out in summer 2008 and sales decrease
Xbox 360----27,000,000