I forgot Nintendo Land existed until a couple weeks ago. Like some of you, I only recently bought a Wii U and after looking at some "what to play" lists for my next multiplayer game, I was reminded of this minigame collection, took a chance on it, and promptly fell in love.
You should absolutely be playing excellent exclusives like Mario Kart 8, Pikmin 3, Super Mario 3D World, etc. but, eventually, you should check out Nintendo Land, too. Or immediately, if you're in need of a game that can bring family/friends together only to tear them apart.