http://www.computerandvideogames.com/article.php?id=172437

Sega believes that Mario and Sonic at the Olympics will sell 4 million units, equaling the feat of the original Sonic title released in 1991.

Mario and Sonic at the Olympics, which goes on sale for Nintendo Wii in November, will pit Nintendo and Sega's flagship characters against one another for the first time, and Sega believes it has a sure-fire hit on its hands.

Bloomberg reports that Masanao Maeda, a corporate director at Sega's gaming unit, forecast that the title will sell 4 million units, although he didn't specify a timeframe for achieving the milestone.

The target is equivalent to almost 20 percent of Sega's games sales during the last financial year ended March 31.

Sales of the title will no doubt be given a boost by next year's Beijing Olympics.

I expect the game to sell decently (Mario Strikers level of decent so about 1 million world wide).  I may be completely wrong but it seems Sega is being way too optimistic.  But then again anything is possible.  It might turn out to be a great game and a sort of successor to Wii Sports as the number 1 party game. 

I don't know about 4 million, but if done well (i really am not convinced just yet) it could do quite well

One major problem I find with it though is that the theme of 'Beijing Olympics' will be outdated by next year, but i guess that doesn't effect people buying games like Madden which are basically relevant for one year

If it's as much fun to play as Wii Sports, with Mario & Sonic. It'll do very well indeed. I'd expect a very high % of Wii owners to have this in there library.

Ultimately it'll depend on how well it's executed, and how well the controls work, but I think the potential for 4 million is there. Funny if this outsells FFXIII and MGSIV.

for me -and i think for a fair few other people as well- its sort of only a second tier game. i might pick it up second hand a little down the track (pun intended :P) but atm im not eager to get it like a lot of other wii games coming out this year.

well, a lot of reviews/people say MP8 sucked (although i find it quite enjoyable with my wife), but its sold over 2 million in US/JPN. Anything half decent with mario will definatly sell.

Remember, there's a DS version too. I could see this game doing close to 3M on Wii and over 1M on DS.

You have got to be joking...??

The Olympics don't even start until LATE 2008!!

Olympics branded games in the past have sold *extremely* well - leading up to, through, and after the Olympics were completed. 

...

I think 4m for this is actually quite pessimistic. Consider that its hitting both the DS & Wii, will draw in both Sega & Nintendo fans - as well as the general public (thanks to the official Olympics license).

Nintendo are publishing this in Japan - and Sega in Europe/US (from memory).

I think (across both the DS & Wii), this will sell around 1m in Japan - by the end of '07. 1.2m in the US. And around 700k (maybe more?) in Europe.

That's 3m sales by the end of '07.

By the end of '08, I wouldn't be surprised to see total sales closer to 7m-8m. And its possible that it could do 10m (lifetime). Will wait and see...

Depends on whether or not the game sucks.

4 mil's a bit too high for me. 2 million worldwide, yeah I can see that. Especially with how well Mario Party does.

I'd say 3 million is closer.