As Wolf said. Sony AND Square have it blocked, as per the article:
"In this case, Square Enix liked PlayStation’s offer best"
More than likely, Sony required it to be exclusive with their offer, because as stated in the article:
"Yoshida says CBUIII wants as many people worldwide to play the game as possible."
But Square is the one with the obligation to Xbox owners. Sony has no obligation to them just like Microsoft has none to PS with deciding to make the games they bought exclusive.
That is how you know its all console war nonsense. If it wasn't Square would be getting the majority of the heat from people that think its a bad thing. But if we did that how are we going to pretend Sony or MS are the good guys and the other the bad buys?