Why must you rely on Text you see on a website or in magazine print?
Watch the video interviews where Mark Rein talks about Ut2k7 on both the 360 and ps3, and where he says "one might run it with a faster framerate while the other might look a little better" and how they will take advantage of each systems strengths, or something like that.
He's said it in atleast 2 video interviews. One was the IGN Uncut panel video that had the 4 people sitting up there discussing the systems. You know, the one where Mark ripped into the batarang, the revolution, all the funny shit
There was atleast one other where him and Cliffy were both taking questions and the gave the same answer.
Its never been confirmed in print, be it on a website or a in a magazine, not that I could find. I tend to believe what the VP of Epic says though, even if websites show otherwise.
Edit: Do you really think they'd Not make a game thats sole purpose is for online mayhem, and skip over Xbox Live? They have much closer ties to MS than they do Sony.