As I said, it's a great racing game and I recommend it. Unless you also have a PS3, because then you would have to decide between Forza 3 and Gran Turismo 5.
Gran Turismo 5 isn't going to be coming out in forever, so for people on the edge about buying either, Forza 3 is the clear choice (and only, if you want a complete game). That and the game is completely loaded with options along with custom decals and stuff like that. It's essentially Forza 2 on crack.
I'm waiting for Gran Turismo 5... Those photos however did make me a bit sick... Like wow. Blurry enough?