The Wii series are a franchise, because they're in a way the same thing. It's everyday titles. Playstation Uncharted and Playstation GT5 would be totally different categories.
And they didn't call it Super Mario Galaxy Wii, did they?
http://www.vgchartz.com/games/userreviewdisp.php?id=261
That is VGChartz LONGEST review. And it's NOT Cute Kitten DS