As early as right after E3 2012 I expected sales to be quite low for WiiU during the first 12 months. Not as disastrous as they have been though, but still quite low. My reasoning was that Nintendo didn't show enough muscles to win over those who had turned their back on them this generation. However, even more alarming was the fact that they didn't seem to have a well concieved strategy to keep those who had adopted the Wii concept. In other words, WiiU as it was perceived at ES 2012, was a product without an immediate and clear audience. Such products meet great market challenges when released.
I must say though, to Nintendo's defense, that I as a consumer find WiiU to be more rewarding product than shown in sales and market share. It definately has its share of entertainment value, but it is too complicated to market as an idea.
I still believe WiiU has great market potential though. It still has potential to become a success story. But time is running out on the Big N.