[quote name='Scrubking']“We don’t feel like the Wii customer and the Xbox customer are the same thing. We think that as soon as the Wii customer turns 14 they want something else.” - John Rodman, Xbox, Product Manager[/QUOTE]
We I think I would put that at 12 or 13, but yes he is probably correct, once you hit that pre-teen age the Wii isnt cool enough since it wont let you swear online the way XBL can.
Which is fine, when the Xbox customer matures at 18-20ish he'll get tired and revert back to just playing whatever is fun. That may be the Wii or it may be some other game. Until then Nintendo will be happy selling to the new audiences they have captured with Wii Sports and other silly games.