I think Mario super6
Mario sports mix
So far, there hasn't been any news on the next "official" Mario game. However, the next Mario game coming out will be Super Mario Sluggers, for Wii. SUPER MARIO GALAXY 2
The next Mario game will come out Late december of 2013 and will be Mario and Sonic: Winter Olympics 2013
Mario Kart nine is the swimmingbird next Mario game.
No One Knows Not Even Iwata (The President Of Nintendo) It May Be Coming Early 2013
Yes there is actually. Mario Party 9 is coming in March. Other games coming soon are Luigi's Mansion 2 and Paper Mario 3DS. The newest Mario games that are already out are Mario and Sonic London 2012 games Wii and 3DS, Super Mario 3d Land, Fortune Street, and Mario Kart 7
the next game coming out on nitrome after "in the doghouse" is "numbskull" and then "bomba"
Nintendo has announced some game called "Super Mario" for the 3DS. You can check the super Mario wiki for more info about this. There's also Paper Mario 3DS coming out! :) :)
The next rated M game is coming out on 5/15/2011
mario party 9
probably
No, there is no Super Mario Galaxy game coming to the 3DS. If there was one coming, it would have already been announced or released.