Nintendo has been extremely adamant about a 2017 release but I still don't buy it.
I wouldn't mind a 2018 release at all, if it means the game doesn't end up being rushed and even more disappointing than XCX.
"Just for comparison Uncharted 4 was 20x bigger than Splatoon 2. This shows the huge difference between Sony's first-party games and Nintendo's first-party games."