GTAGaming.com has collated all of them and provides selected highlights. The isometric view will be joined by a steady 30 frames per second, weather effects and day / night cycles. As for the soundtrack -- a franchise staple -- there are some instrumentals of licensed songs, but nothing to write home about. It also doesn't seem to shy away from the F-bomb, according to IGN.
The wanted level is handled very differently. While you still need to outrun the cops, you're now also required to send a few cops shuffling off the mortal before you'll lose a star. And yes folks, piloting a helicopter makes a very welcome return.