Super Mario 3D World.
This game is fantastic. I am a straight up sucker for platformers that is for sure, and Nintendo knows how to do these things properly. It's not just regular Mario though, it's the first 3D, multiplayer Mario game, and from the brief bit of time we spent playing multiplayer, it is a million times more fun and less frustrating than New Mario Bros U was.
Thus far the level designs have been fantastic, the music is brilliant as per usual (thanks Koji Kondo) and getting all the stars and stamps on every level has been easy so far, but I am certain that it is going to get far more difficult. Will Super Mario 3D World save the Wii U and be the system seller that Nintendo wants it to be? I'm not certain, but I will have you all know that this game is phenomenal, fun, and should be played by everyone. Expect a full review soon.