Cheers. Ok that's a very telling interview - he seems genuine about no game being in development at that time. I was certain Retro would be working on it already, since we don't know what they've been up to since Donkey Kong: Tropical Freeze (or do we?).
So no Metroid before 2018, that's one down from the killer launch year lineup I was expecting for NX. Zelda will be cross release like TP was. 3D Mario might not make it for launch (holidays '16 will be 3 years from 3D World's launch, which is tight, considering NX is an all new system). Splatoon won't take as long, but still the original was too recent. Maybe Smash, surely not Mario Kart. 2D Mario will get a rest for some time, people are tired of it, and Mario Maker kinda reset the whole concept. Similarly 2D Donkey Kong seems due for a break. Maybe Pikmin, which doesn't move any systems though. Not Paper Mario, they just unveiled the Wii U game.
What else could they be working on? F-Zero, after the tease in MK8? A proper Animal Crossing?