The Wii is aimed toward more casual gamers. You have to find out what kind of gamer your son is. If he likes more complicated games or a wider library, get him an Xbox 360 (keep in mind that they are expensive). A PS3 pretty much works for everyone, but had fewer titles than the Xbox (although they have exclusive series like Little Big Planet, or my personal favorite Ratchet and Clank. ) If your son likes ping pong and tennis, or baseball, or movement inflicted games, then a Wii is an alright choice. Just keep in mind that the Wii isn't exactly up to par with the graphic standards like everyone else is.
That's my input.
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Hi there! Please refer to me as Moss. Unable to change my username to reflect that change. Have a nice day. <3