according to major nelson that is. If someone gets it let me (us?) know how it is, I dont have a gold account anymore and have to wait a week (or however long it is).

It's not awful!

A game where I can finally play as Ryo Hazuki again?!?!??! Count me the fuck in!

I should elaborate. 
 
Game seems to play fine, the weapons seem to be a little underwhelming in their design, but they may just be what's available in the demo.  
The single track is all right; bright and colourful, capturing the source material's theme well. Usual mix of jumps, turbo pads and corkscrews.  
The full track list is available to scroll through, but it seems limited in its scope, only predominately features tracks from Sonic, Jet Set Radio, Super Monkey Ball and House of the Dead. 
Sonic and Banjo/Kazooie are playable in the demo, but didn't really notice a difference in handling between the two characters. 
Didn't get an All-star power-up so I didn't get to see them weapons, although a few of the CPU players did. Banjo rains jiggies down on the track and Beat roller blades around spraying paint. 
Sell screen lists that it features four-player split screen, so I could see this scratching a Mario Kart itch for people without a Wii. 
 
Easily a three star game, maybe four if the full game has a decent singleplayer progression and the tracks are compelling enough to warrant replaying. 

Don't have a gold account, but this is something I'd check out (especially on a snow day like today). Is it any good at all?
 
Seems like these non-major Sonic games are better than the major ones.

okayzz gonna talk about this here. looks like a fun game

Demo was pretty good. Default difficulty is set to advanced though so some people may wanna change that.

Found it pretty fun. The one level you get to drive in, is colorful and lively. There's a lot goin on all the time. Unfortunately did the framerate take a lot of hits in general. 
 
Besides that is it a pretty good Mario Kart clone, with a really great presentation. Looks like it could turn out to be really fun, and as someone else said, a good alternative for those without a Wii.
 
Btw - Banjo/Kazooie has more top speed than Sonic for some reason (though he's acceleration is maxed out)...

Obvious Mario Kart clone, but a lot of fun.
I personally had no problems with the frame rate but Sega have said it's not the final version of the game and have promised it will be improved by the time you play the actual game.
 
After Darksiders, Bayonetta and Mass Effect 2, it seems like a good change of pace.

" Obvious Mario Kart clone

It was pretty boring to me, except for the announcer. Was that dude Adam West?

"  
 Here lies 10 mins
  

Premier Contact HD Sonic & Sega All Stars Racing
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"

Well, I am not gonna get this, ever.  Even if in the bargain bin.  But it was an ok demo.  Complete Mario Kart clone, down to what they weapons do.  They have mushrooms (running shoes, in 3s), the green shells, the bullet bill even appears making you super sonic.  I just dont know who this is gear toward because its not like all these characters were ever really all stars.

" "screw father, I just wanna race"  Gettin bought. "

It's alright...

Why is Banjo in this game?

" Why is Banjo in this game? "

This really isn't something to consider buying. The demo has a very unfair balance of difficulty. No matter what difficulty you play on, somehow the AI always puts up a big challenge. This will certainly be a miss from me.

I love kart racers so I'm quite excited for this game.

The big problem I had with the demo, and pretty much the one reason I won't even be considering a purchase, was the choppy framerate. I can handle some choppiness in other genres, but I don't think the amount I saw in the demo is anywhere near acceptable for a racing game.

i need to try this out. ryo hazuki better be in a forklift!

It's fun.

The demo is fun and the game looks great the only thing is it is hard as hell.