Tons of exclusive games, I'll just list a few I've played myself and I think worth giving a shot:
Zombi U - Awesome Survival Horror experience, not everyone might like it but it's a true hardcore game.
New Super Mario Bros. U - Might not be your perfect 2D platformer, but it's one of the best recently released
Lego City Undercover - Free Roaming Open World LEGO with tons of jokes and humor, all packed in an incredible gameplay focused package (what it really misses is co-op)
Pikmin 3 - Probably the best in the franchise, too bad it ends when you really stlil want to play more!
Wonderful 101 - Kamiya and not only that, pure action, humor and a truly satisfying game. Hard mechanics, though
TLoZ: The Wind Waker HD - Awesome remake of the original GameCube Game, pretty graphics and a true adventure game.
Super Mario 3D World - Super fun in co-op, awesome graphics and one of the best 3D Marios ever created, period.
Donkey Kong Country: Tropical Freeze - Best 2D platform game ever created, Retro-awesomeness, pretty graphics and if you like challenges it could really last a lot more than just the storyline.
Mario Kart 8 - Do I even need to tell you why?
and don't forget there are more games coming, just to list a few:
Hyrule Warriors - Sept
Bayonetta 2 - Oct
Super Smash Bros. - Nov/Dec (Winter 2014)
Captain Toad - Dec/Jan
Xenoblade Chronicles X - 2015
TLoZ U - 2015
Splatoon - 2015
Do you really need any more reasons? :O