This game is hyped in China (especially because it is a game that takes place in China and the immense hyped Beijing olympics).

The thing is, every single Mario Party game has sold over a million, with 5 out of 8 selling over 2.

http://vgchartz.com/worldtotals.php?name=mario+party&console=&publisher=&sort=Total

Mario Party is a proven franchise, and 8 came out around a time where there weren't very many Wii games.

However, Sonic and Mario at the Olympics will come out during a very hot period, with several AAA games. It could easily sell over a million, but Sega will be sorely disappointed if they're hoping for 4.

 double at least...

The thing I am more curious about how will this game score.

http://wii.ign.com/articles/821/821021p1.html

http://www.gamedaily.com/games/mario-and-sonic-at-the-olympic-games/wii/game-previews/preview/5933/20463/ 

http://wii.advancedmn.com/article.php?artid=10434 

I completely agree with you Montana.  There are just too many other games that have the same or even greater mass market appeal and much better core gamer appeal and review scores.  The game may even be scored highly and be really fun, but it's just not going to be able to compete on the Wii with the kind of games that will be out at the time.

I expect the game to do well, but by well I'm thinking 1-2 million lifetime.  That's not bad, but 4 million ain't happening.

in their dreams.

but seriously, if they want to sell 4 mln, they'll need multiplayer online. of course, it still wouldn't be enough. they should be ecstatic if it comes close to 2 mln.

There are just too many other games that have the same or even greater mass market appeal and much better core gamer appeal and review scores. The game may even be scored highly and be really fun, but it's just not going to be able to compete on the Wii with the kind of games that will be out at the time.

Yeah, there are about 6 or 7 really big games on the system... But they can all sell 4 million! Go Wii!

The big ones...

Mario Galaxy
Smash
Metroid
MySims
RRR2
Guitar Hero 3

And in Japan...

We Love Golf
Wii Fit

It's a pretty packed lineup, yeah... In perfect conditions, all of these games would reach 1.5M... Is there anything else that could reach that number?

Edit: Of course there is.

Link's Crossbow Training
RE: UC

I believe that Sega is being (way) too optimistic but this game has a ton going for it:

1. Massive licencing; Mario is still probably the largest videogame IP in the world being that 5 million games based on the Mario IP have been sold this year in North America alone, Sonic is tainted but still has a lot of fans, and The Olympics is a huge IP on a world wide basis.
2. Popular System; the Wii will likely continue being the most popular non-portable system by a wide margin when this game is (reasonably) new.
3. Popular Genre; mini-games and party-games have been very popular on the Wii (Wii Sports, Rayman, Mario Party 8)
4. Christmas Sales; many people will be buying the Wii as a gift this christmas and will likely buy Mario and Sonic at the Olympics along with the system because it seems like a safe gift choice.

I think it should be fairly easy for Sega to sell more than a Million copies, as it moves towards 2 or 3 Million copies it will need to be a reasonably polished fun game, and to pass the 4 million mark I think it will need to be the best party game released on the Wii in Q4 2007.