Most likely? HA! The NX whatever it will be, WILL NOT LAUNCH until AT LEAST Q3 2017. The next Zelda game will be released in 2016. Most likely Q2.

And WHY won't the NX launch next year? Simple: too soon. There are no third party developers working on the NX at this moment. And won't until E3 2016. It takes at least a year to develop a game for a certain platform, so... This means that if the NX launches in 2016, it's launch won't be better than the Wii U's launch. And a good launch is required for a console to be a success.

Nintendo will however also release the same Zelda game as a launch title for the NX.