There are alot of new features, to create a player, u must do the 40 yard dash, banch reps, etc. and stuff like that go to IGN and watch the video interview with David Ortiz, (producer, black guy, not red sucks power hitter)
Superstar mode sounds just like ESPN NFL 2k5's First person camera view which is awesome. Hopefully you'll have better lateral movement as a defensive back though.