As mentioned in the WWDC keynote, Apple is adding official support for game controllers in iOS 7 which is going to be awesome and I can't wait to get my hands on one. You know what's going to be even more awesome though? Game controllers for the Apple TV.
Here's how I bet things play out:
After iOS 7 ships game makers are going to start adding support for the new controllers (duh). This is probably going to take a bit of time though, and they'll work out the kinks and within a year all the popular games will be on board.
Then two or three years from now Apple introduces a new product category. But it's one we already know— the Apple TV. It might have a different name but it's basically the same little black box with an ARM chip in it and storage— basically an iOS device which uses the TV for output. And it has a game controller. And there's already a million games that we know and love which are using the new controller, and all these apps are pretty much ready to go on day one.
And then the existing console makers crap themselves, because all their casual gamers just disappeared.