Coming from Nintendo's financial statement...
"Beginning in March and continuing through the rest of the calendar year and into 2014, Nintendo will release a cavalcade of strong, fan-favorite software titles for both Wii U and Nintendo 3DS. New entries in the Mario Kart, Super Mario, Legend of Zelda, LEGO City, Wii Fit and Pikmin franchises will help Nintendo regain momentum for Wii U. Additionally, highly anticipated Nintendo 3DS games such as Luigi's Mansion 2 and Animal Crossing: New Leaf have the potential to be hardware drivers and bring new audiences to the platform."
The only problem with this statement is, we have no idea just how far into 2014 Nintendo is talking about. We could see Mario Kart this holiday season, but maybe Mario's next outing won't hit until deep into 2014.