It seems like Nintendo was caught off guard in their surprising Holiday success, because according to GamerLife the Wii U is in short supply in their home country Japan. According to the article, Amazon Japan, Yodabashi, and Tsutaya are both currently out of stock of Nintendo’s home console. Not only that, but Twitter is a flurry about a lack of stock on mom-and-pop store shelves.
What does this mean? There are two options — the first (and most unlikely) is that they are winding down production of the Wii U in anticipation of Nintendo’s upcoming console. What is far more likely is Nintendo was surprised themselves, given the success of Super Mario Maker and Splatoon in Japanese markets, and are momentarily being caught with their pants around their ankles in the months after a considerably successful 2015 holiday season.