Kart racing games used to be amongst the most miserable thing to happen to a franchise and their much loved characters. Eventually, with the exception of Mario Kart, the whole genre died off with not really any examples this generation.

Sonic & SEGA All-Stars RacingSega are willing to buck that trend and to help them out they enlisted Sumo Digital who have been responsible for decent games and revivals and deliver appropriate levels of fan service.
Sonic and SEGA All-Stars Racing or Sonic Racing will attempt to make use of 22 of Sega's most loved characters, giving them complimentary vehicles and special moves and letting them battle it out 24 tracks inspired by those same characters. To that end you get choose from the likes of Tails flying a bi-plane, Jacky from Virtua Fighter in a car that looks like a Ferrari and Ryo from Shenmue driving a forklift truck.
In the demo you get to choose from Sonic or Banjo & Kazooie for a 3-lap race on the Lost Palace course, which is inspired by classic Sonic levels. Lost Palace features loops, jumps, bumpers and speedup pads as well as art and other features fans will recognise.
In single player you race against 7 others and you get the standard kart racing controls including a drift mechanic that boosts your speed if done correctly. The power-ups include items usable by all characters and some character specific boosts. Whilst it's hard to be original with the power ups, Sumo have tried with the attack that turns your screen upside down worth a mention.
The controls feel reasonably good, but the course you start on is certainly not a beginners course; I was finding it difficult to finish in the top half of the roster, losing places to collisions with walls. It's hard to determine from the demo how game changing the special moves are and how much rubber banding is going on.
You also get to try out the 2-player split screen mode that works well enough and the final release will support 4 local players. Online the game will support up to 8 players at least on PS3 and 360, but this wasn't available in the demo.