This could be THE best cart racer, but . . . .
The graphics are fantastic. To be able to create new mods & import popular characters to race with, is just plain off the hook! The track creations are wicked, at the least. Wherever your imagination can take you with a race track, you can manifest, & give racers all of the havoc they won't ever be ready for!
I can live with the ditty bop music that comes with it, even though most racing games are providing the feature to use your own music playlist on your hard drive as the soundtrack (see NFS: HP).
I can live with the fact the AI characters becomes invincible on certain tracks during the career (especially when you get into the 2nd half of the the career, nearing the finish), as if the tracks, themselves, were not already challenging enough.
What keeps this from being a replayable game, for me, are THE LOAD TIMES!!!!! The load times become so bad, that it leaves you to question if the PS3 has locked up & crashed on you. You can start a game to load, & walk away . . . FOR A LONG TIME! It only gets worse with the updates that are added to the game. In addition, getting online with it, can be an arduous task, as there is generally something wrong with their server (unless it's ALWAYS packed).
Overall, a nice game. If they can truly provide a patch that can REDUCE the load times TREMENDOUSLY, then it can be in heavy rotation.