Looks like ShopTo has cast their lot to get in preorders of this new product early.
May look the same as Skylanders and Disney Infinity but Nintendo's take on the 'toys to life' category differs in the sense that characters are usable across different games rather than being tied to a particular title.
Confirmed support for:
Super Smash Bros
Mario Kart 8
Mario Party 10
Captain Toad's Treasure Tracker
Yoshi's Woolly World
Also, I've seen some confusion about this but these characters are completely optional for gameplay.