Mario & Sonic at the Olympic Games has been a huge success: a cross between the great first week sales of core titles and the long tail of casual ones which will certainly beat the 4 million mark worldwide even before we get to the Olympics (where another boost in sales will happen).
However, this is only the beginning.
They didn't use many of the events they could have: for example doubles table tennis, other kinds of rowing, other kinds of shooting, various martial arts, various team games (beach volleyball!), cycling, badminton, and of course some more dream versions of existing events.
They also haven't even touched on the Winter Olympics - there are many, many events there too.
Finally, future Olympic Games will be held in other places.
So, Mario & Sonic could in theory come up with (I estimate) four sequels over an eight year period without running short of new material.
Mario & Sonic Winter 2010, Mario & Sonic 2012, Mario & Sonic Winter 2014...
It's Sega's lifesaver, I think. Perhaps they could use the money to revive all of their old franchises for the Wii and DS in a way that actually takes advantage of the controls.
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