It was just a matter of time, with the game in the hands of quite a few gamers, and being streamed in several places, it was inevitable that someone finally managed to get to the point of obtaining an unannounced power, and it was just as inevitable for the information to end up on NeoGAF. It’s the downside of the revolutionary social features of the PS4 (and of the Xbox One).
Since the nature of the spoiler, the power won't be revealed directly in the article, but you'll have to go through a little minigame to find out, at your own risk.
Please don't spoil the power in the comments. Let only those that really want to know find out.