Hmm..not sure. I've never played the console version since i don't have a console. But yeah i've heard it's pretty much the same as flatout 2. There must be something different tho. The PC version might be different.
I have the console version and the main difference is the addition of the challenges which include beat the bomb (get through as many checkpoints as possible before your car explodes), derbys (with added powerups which make you super heavy, repair your car etc), and events. I believe there are also more cars on the track but can't remember exactly.
Other than that I think all the tracks are the same :S. I think the events are probably new though. Been a while since I've played it - got too many racing games