^ The thing that springs to mind is that the 360 hasnt got any games from good developers that have gone for realistic graphics.
Big games like Halo 3, Gears 2, Mass Effect all went for art direction. KZ2 currently wins at the moment, but I bet my bottom dollar the 360 will have a couple of games that beat it's graphics this year. Mainly Alan Wake and Forza 3. Also I believe Risen will to.
Personally KZ2 is the ONLY game on PS3 that is better than 360 games. Gears 2 for me was and still has the best wow moment ever for graphics.
Mass Effect 2 will undoubtly look astonishing also. CRYEngine 3 games for 360 will also beat KZ2. But then PS3 will continue to improve as well. By the end of the gen both consoles will not outshine the other.