Ok, here's what I have to say:
SuperSonic just looks like an alternate skin, and he dosen't have any cool effects.
Every vehicle is just a reshaped version of an existing one (Airboards; Ghost, Bigfoot; Scorpion, Tornado 2 combat mode; Banshe)
The animation just dosen't look natural, Sonic walks as if he's wearing Hoverskates.
All the level remakes are still essentially 2D.
Alot of that promotional footage was from completely different games.
They seem to be using the netplay combatibilty as if they're the first Sonic game with netplay.
As has been said, the gravity is way too low.
Oh and by the way, the emission on that airboard is all the way up, which means it glows (crappily), and it can't be shaded.