I do understand the horses for courses arguement, but the number of launch titles seems a bit low.
The Wii went down a storm in our house and was played by 5 people vs 2 for the XB. It does get an outing every now and then for Mario Karts but the two eldest left home a few years ago and the XB went with them. I think both only play PC games these days.
My youngest (18) has brought her DS with her to Cornwall this week to play Pokemon in the car. Thankfully she gave up the dog training game years ago (it was a voice controlled job).