Released for consoles and PC, plus Nintendo's Wii, back in August last year, Disney Infinity is Disney's version of Activision's Sklylanders franchise. It works as both a video game and a type of collectible figurine hobby.
The second game, Disney Infinity: Marvel Super Heroes (also know as Disney Infinity 2.0), is due for release on 19th September in the UK, and 23rd September in the US. However, it won't be available on Nintendo's Wii, only the Wii U. To make up for this Nintendo have offered Wii U owners the opportunity to download the original Disney Infinity via the Wii U eShop, completely free.
You will need the Infinity Base and at least one figurine, however, so this free copy won't be worth anything without them. But it's good news if you've built up a sizeable collection of figurines with the Wii version, and want to continue using them on Wii U.
Disney Infinity 2.0 is backwards compatible with the first game's Infinity Base and figurines too. Do note however that the base for the Xbox 360 version won't work with the Xbox One, so you'll have to buy a new base.
Toy Box Trailer - Disney Infinity 2.0
Disney Infinity 2.0 is due for release on 19th September in the UK and 23rd September in the US, for PS3, PS4, Xbox 360, Xbox One and Wii U.