atomicblue on 07 September 2015
I doubt this will be part of Nintendo's Wii U successor (whether that's NX or something else). It wouldn't be that surprising to see it on Wii U some time next year, actually. Nintendo would already have had a lot of assets from Pikmin 3 that could potentially be used for the next game, and that's easier if it's being coded for the same machine.
