I won't number it but
360 > Wii > XBox > GC = PS2
And for 360 and PS3 comparison, if you asked me two month ago I'd give 360 something like 13~15. But recently released multi platform screenshots I'd have to cut down to 10.
Now it comes down to individuals taste, for example, Rainbow Six Vegas, 360 version comes with excess amount of blur, which I'm not very fond of. Gun models lost their sharpness and looks like they're made of rubber. But PS3 R.S.Vegas lacks motion blur. So comes down to wether you prefer excess blur or no blur.