The latest game featuring the fine art of turning left isn't remarkably different from its improvements-packed predecessor, though it does have a few small additions.
Most of the modes and features from NASCAR 06: Total Team Control return in NASCAR 07: online racing, Fight to the Top mode, team controls, voice command recognition, rivals, car swapping with teammates and driver attributes that affect overall performance. The minigames have been replaced with challenges based on real racing moments introduced by actual drivers.
Many of the bugs have also been worked out so cars are less jittery (especially online), the game rarely freezes and there are fewer annoying in-game animation sequences. The jitter you do see is caused by looser car controls, making it difficult to drive in a smooth, straight curve until you win many races and improve your driver's attributes.
Less emphasis is placed on the racing squad this time around so that if you corner well, play nice and drive bump free, you'll fill a Momentum Meter that will improve your driver's speed and handling through an entire season.