Now it’s 2015, and Shigeru Miyamoto has let slip that Pikmin 4 is in development and in fact very close to being completed. Nintendo then had no choice but to back up Miyamoto’s comment and confirmed that Pikmin 4 is indeed real. What nobody is saying is when the game will be released and for which platform.
In that regard there are three choices: another Wii U game, a 3DS game, or a launch title for the NX. A lot depends on how far along in development Pikmin 4 is (what does “very close to completion” really mean?), but a Nintendo NX launch title would be great (for Nintendo). Fans, of course, will want it sooner for an existing platform. The NX is expected to be something Nintendo only starts seriously talking about in 2016, which points to Pikmin 4 being a game for an already released platform. My money would be on another Wii U game.
Another way to look at this news is Pikmin 4 is nearly complete, meaning the Pikmin development team can move on to Pikmin 5 soon and potentially finish it in time for the NX launch. If Nintendo is going to talk about the NX next year, it could be a console launching in 2017, potentially allowing a two-year development window. That’s achievable.