This has been known from the get-go. They said that practically at E3.
I'm skeptical that it would ever go anywhere else. One, in order to use Smartglass, you have to have multiple devices. You'll need a controller AND the tablet, and swapping back and forth as much as ZombiU will require is going to be incredibly tiresome.
And two, the game is WiiU-branded. Sure, they can remove the branding, but it's not the same then.
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