Nintendo has reaffirmed in a fiscal briefing that Zelda Wii U will be released sometime in 2015. The report did not specify when in 2015 this may be, but confirmed the release window for all major territories: Japan, Europe, and North America.
It will most likely be during the latter part of 2015, given the fact that the game has not been playable as of yet. The franchise also has a history of holiday releases, with Ocarina of Time, Majora’s Mask, Twilight Princess, and Skyward Sword all being released during the holiday season.
We first saw the 2015 release date in the game’s original teaser. Hopefully the game isn’t plagued by delays like previous Zelda installments and comes out some time next year!