A lot of people have input on this. I definitely want to try development on XB1, PS4, and even Wii U if possible.
Since I can't /promise/ these will happen (developer account red tape and the fact that I can't test any of these consoles on my own), I'm leaving them off the stretch goal list.
But anyway, the final goal is to use Unity to its fullest and sell on everything. The digital download for backers will be solely PC/Mac/Linux, though.