Gamesradar received some hands-on time with Sonic Generations in its near-complete form recently and was nice enough to do a write-up of what they’ve seen so far. Things look promising: the jump height issues have been addressed, running up curves now has some basis in reality, the 3DS version has received a major revamp, and the plot is thankfully non-melodramatic (spoilers in that link, btw.) Additionally, there’s more information on Doppleganger races and optional missions (complete with unlockable content) over at SPoNG.
But really, the main attraction here is seeing Classic Sonic play through Sky Sanctuary Zone. Let’s go! (Sorry no embed, Gamesradar’s JavaScript doesn’t appear to be working.)