A major title like CoD serving up 720p instead of 1080p on one console and not the other looks pretty damn compelling at first.
However, the answer is in the article. They didn't have an Xbox One to develop and test against. They just ran some tests on both systems when the game was fully completed. The magic for these systems is when devs optimize for them, which is why I'm inclined to think that game performance differences are going to be negligible.
Who am I, though? No one but a dude with a XB1 preorder and a dream.
I'll probably buy the PS4 too anyway.