Nintendo's Mario Tennis and Mario Golf did really good, so Nintendo announced that they will be making a Mario Baseball game next.  The question there after was... what would be next?  Football, basketball, hockey,paintball (my choice), la crosse... ?
IGN is reporting that Basketball is indeed next...  but get this, the Nintendo charcters will be in EA's next hoops offering on the gamecube - NBA Street V3.
I heard that Soul Caliber 2 on gamecube sold better than on PS2 and Xbox.  Simply because Nintendo's beloved Link was in the game.  So I'm gonna guess that this game will do good.
Link