MY REVIEW:
This game is fun, but at some points frusterating. I always seem to "pop a wheelie" when I launch. Some of the challenges seem horribly impossible (and the rewards are either very good, or very lame). It's still nothing like actually riding.
I'd like this game if it were more like the Gran Turismo series. Where you could buy commercially available vehicles (or even be able to modify them). Every bike in this game is from Moto GP, and you can't modify them (other than gear ratios and suspension), so no aftermarket parts, etc.
It's a fun racing game, but it doesn't stack up to Gran Turismo, or anything like that. More pictures in the game, of that girl on the cover of the box would be nice (you can get some through winning challenges ;)).