I feel like it has. Let me explain, PS4 may end up more powerful, but I just think it's pretty clear the difference will not be that much.
Too most casual users, they wont see any difference. PS4 and X1 will be the "same" power in their eyes.
Can anybody REALLY say there is a big difference between Forza 5, Killer Instinct, Ryse, Dead Rising 3, and Knack, Drive Club, Killzone Shadowfail? Sure some fanboy warriors can claim there is, but I dont think so. They are all "next gen".
And thus Microsoft has "won" the graphics war imo. They did what Nintendo failed with Wii U, make a console that is "good enough" and will get all the ports.