Skullwaker on 25 March 2015
Man, I really don't know. It has some titles that will surely get to a million but haven't yet (Captain Toad, Pikmin 3, Lego City, Hyrule Warriors), some that are more hard to predict (Bayo 2, ZombiU) and upcoming games that should hit the 1m mark (Zelda, XCX, Yoshi, Mario Party, Mario Maker, as well as possible releases like Metroid, Animal Crossing and Paper Mario). Given that there's 9 right now, I think 20+ is possible when you take into consideration the games it should get.
