Well, here's how Mario got where he is today:
First, he had a bro. No, scratch that, he had THREE bros.
Then he got a few lands.
Then he got a world.
Then a 'sixty-four!', whatever that is.
Then he got a sun.
Then he got a NEW bro.
Then he got a Galaxy.
Then he got ANOTHER new bro.
And he's got a Galaxy, too.
All this points to a New Super Mario Sis's Wii.