My father bought my little brother a playstation 3 for xmas - But i can tell my brother just wants a Wii since its 10 times more fun and all his friends talk about them and all the extras they have.
Lets face it Ps3 is old hat now and boring. Who cares about graphics when you have all the Wii nunchucks and balance boards etc. The wii is revolutionary and it can even unite a family around the TV in hysterics.
Go with the Wii - They even make it cheaper so what have you got to lose? i guarantee he will have so much fun he wont care about graphics when he gets the bundle and add ons.
Here is a great site to help anyone Buy Wii
Its rather funny too.