imo Mario Tennis has always been the best Mario Sports franchise, and I have not heard about a Wii installment. This game sell millions (3-4 million) because of the Motion controls and it would tap into the casual WiiSports crowd in a major way(Mario + Tennis + Wii = surefire success).
I would hope that it is similiar to WiiSports tennis in gameplay mechanics, but it would be deeper, and have some sort of a cheesy story mode.
End of 2009 Predictions (Set, January 1st 2009)
Wii- 72 million 3rd Year Peak, better slate of releases
360- 37 million Should trend down slightly after 3rd year peak
PS3- 29 million Sales should pick up next year, 3rd year peak and price cut








