A brand new Pokemon game, first and foremost.
A new FPS, perhaps another Moon, Dementium, or Metroid Prime game
Mario Kart is a given
Zelda is a given
Smash Bros
A clubhouse games that takes advantage of 3-D could be cool.
A NSMB game that is sort of a 2.5D, in that it is a side scroller but you can move in 2 or 3 layers, like in the background. You go in pipes to move from layer to layer.
A new Hotel Dusk Room 215 or Professor Layton mystery game that uses the 3-D (walking around a hotel looking behind furnature for clues, things like that)
A portable Mario Galaxy (Wouldn't be surprised if this gets made, since the hardware will be 3-D and Nintendo seems to enjoy making these games)







