Mario Tiddlywinks!!!
I've already stated my opinion on this subject, and no more needs to be said.
The argument was posed that the reason why we haven't seen many (good) Mario games is because the two Zelda titles have been consuming so many resources. To be honest, I would rather see a new Zelda game than a Mario game. Shigeru Miyamoto has yet to allow his Zelda series to be infected with useless and wasteful titles like he has with the Mario series.
In other words, we know that the next Zelda game will be phenomenal, whereas it's anyone's guess as to when we will see a good Mario game (with a plot).