See I have a sliight doubt about that because this person who's making it writes that he feels that Sonic Team did not do a good job bringing Sonic to 3D, and that it may even be impossible to make Sonic work in 3D, but that he will try his best anyway. And here we have Sonic seen walking backwards, which is... o_O
"I'm nothing to say this but I think that Sonic Team have not completely succeed to manage the evolution from 2D to 3D. In fact the Sonic gameplay is hardly convertible to 3D. But I'll try another way to do it. ( = more freedome, more movements, another kind of control, more speeeed )."
Anyway I reckon he has attempted to retain the sense of momentum from the 2D games. He probably succeeded, too! For whatever it's worth.