I see no reason for them to buy SEGA. SEGA isn't exactly a very good company anymore. They don't make a lot of money - and what they make is on Wii. They're likely to keep going on Wii for a while.
High Voltage is a risk buying. With the massive hype, Nintendo could lose some PR by buying it if it flops. Also, they aren't likely to lead to big sales.
http://www.vgchartz.com/games/userreviewdisp.php?id=261
That is VGChartz LONGEST review. And it's NOT Cute Kitten DS







