hmmm.. well i'm not a ps3 fan but it just looks like the gamma is set way high on the ps3 and normal on the 360. the high gamma would cause the colors to look washed out like the terrain in the beginning
I just watched the comparison and the PS3 version did look a bit washed out. I thought the XBox360 version was a bit sharper and the colors looked a bit better (of course do to the washed out look). If you watch the explosions then you will see the difference I'm talking about. Still, you have to remember that the PS3 is still pretty new and should improve with time.
Reset the TV on those and let me see it again. Although it should be noted, I have never liked mech games. I don't know why though.