Not that I'm gunna play it anyway, but I hope this is going to be "open world". Of all the directions the series could have gone, truly open 3D environments to dash around in, with environmental obstacles to do tricks off of feels like a no-brainer we should have gotten by at least ten years ago.
Closest we've gotten is Sonic Boom!, and I hope the flop of that branch of the franchise didn't chuck that possibility in the bin.