UPDATE: Steve Lycett under his S0L tag has over at the SSMB cleared up the Showtime Events part of the preview –

Showtime Events eh?

Ages ago we did have something like that as one design proposal – where through the race the commentator would announce something to mix things up – but it never went into the game proper. I think you can safely ignore that one!

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S0L
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/UPDATE END

Original artice below –

Sonic fansite Spindash.de have posted up what’s labelled on their front page as a preview of Sonic & SEGA All Stars Racing but links to more a general information page for the game.

The following translated information is listed –

It will either be represented · some Sonic characters and some familiar characters from Sega Franchais.
· Richard Jacques (Sonic R, Sonic Chronicles), the music composed. Bentley Jones sings the title song “So much more.
· On all consoles online use there should be a Onlinemutliplayer mode, where you can race with 8 players against each other. Local multiplayer can be four players to play against each other. Probably it is in online mode, the DS version to play only four of us can.
· Overall, there will be 20 characters and 24 tracks
Each character has their own vehicle, including race cars, monster truck, motorcycle and much more.
· All-star action: Each character has a special ability that helps him catch up if it is a little further back. Sonic turns into Super Sonic, Beat can go on his skates, etc.
· Showtime events: This can also be used if one lagging and it affects all the other drivers, in total there are 26 Showtime events. These include for example Reverse a Roo, Little Big Lap and Melee Madness
After each race you earn · Sega miles, can be used in a shop for more characters, tracks and songs to buy.
· There is a narrator who describes what is happening on the track. Who does not want him to hear, you can disable it.
· In the single player there is next to the Grand Prix calls a mission mode and a Time Trial.
· In an Art History section you can about all the characters and their field games

Bolded are the points we’ve not heard much about such as the History section which as far as I’m aware has only been briefly mentioned and not much about what it contains.

The SEGA Miles currency to buy more characters, tracks and music is re-affirmed.

Completely new are the Showtime Events which translate poorly but we can gather that they apparently help with lagging(in online races maybe?), there are 26 of them and they each have names such as Reverse a Roo, Little Big Lap and Melee Madness. For now if they are actually in the game we’ll have to wait until more information is revealed to clear things up. We’ll update you when we know more.