Along with many things of great news, Nintendo has been on a roll with their sales. Hyrule Warriors exceeded expectations. Smash pre-orders have increased majorly, both of these noted have boosted Wii U sales majorly. The 3DS version of Smash has reached 3 million units sold as well as...Tomodachi Life. 3 million units may not seem like much for the amount of time it's been out, but 3 million units isn't even something you'd expect a game about putting Miis on an island resort to make friends and family to do. Tomodachi Life is doing so well, Iwata expects it to do even better by year end sales. He also noted that it's set for some long-term growth. With the way things are going, I'd actually expect a new Tomodachi Life to make its way to the Wii U in the near future.
Source: http://www.gamnesia.com/news/iwata-tomodachi-life-can-continue-selling-well