Didn't they try that during the GameCube era? You had Pikmin, Animal Crossing, Luigi's Mansion, Eternal Darkness, Custom Robo, Cubivore, Doshin the Giant, Battalion Wars, Geist, Chibi-Robo, and Odama. That is about two notable new IP's a year for the GameCube. But the GameCube still only had about 10% marketshare, and the best-selling games still had Mario on the cover.
I don't care if Nintendo makes ten new IP's a year for the Wii U or none for the rest of the console's existence. Nor do I think it really matters. Nintendo just needs games that lure people into making a $300 purchase and/or putting down $50 or $60 for a game along with a million or so others.
Later on, I think I'm going to make a thread called something like "Games Nintendo needs to make for the Wii U that they haven't announced yet." The majority of those games will be sequels or otherwise be iterations of existing franchises.