This game is awesome.
They added lots of new stuff since the original TMN. Dirt, water, new boosters, 3D mode (you need red and cyan glasses, not red and blue ones) and much more.
By the way Zad, you can still download 3D models and put them into the game. I've downloaded a car designed for TMU and it works.
My account's name is echothefirehog.
Also, I'll upload my tracks soon, unless I forget to.
@MrMr: You don't know what you loose. Some great hours of F1 awesomeness.
EDIT: I've sent a friend request to you, Zad.