Like always, check out the games that are out on both consoles and choose whichever one has more or interest you more.
In my position, I went with an PS3, reason because I already have a PC, and most 360 games gets ported to PC. The only game that interested me on the 360 was the Forza series. The 360 exclusives like Fable II, Halo 3, and Gears of War 2 does not interest me at all. I have all the seventh generation platforms in my household by the way
, 360 is the only one I do not own.
I think both consoles has great graphics, I couldn't tell them apart either. No consoles is better than the other unless the game devs know how to fully optimize it, and has games with great gameplay and replayability (the two things I look for). Graphics is so-so to me, not a thing I look into.