I'm checking it out. So far, I'm pretty impressed. It has the look of the old GTR mod to F1 2002, but the physics don't seem quite so arcadish as F1 2002. Remember though, this is not a mod - it's a full up game in its own right.
The sounds are really nice. The force feedback is really cool - you feel engine vibration. And the graphics are drop dead gorgeous - the trees look absolutely real. (I'll post some screens later.)
The damage model looks a bit off (or just kind of basic), but I haven't tested it a whole lot. The cars themselves may be too pretty - really shiny pieces of work (a bit odd looking to my eye).