I've seen all three in person (except the Rev was black) and I have to say:
1) Rev
2) Xbox 360
3) PS3
Where the gap between Rev and X360 is a lot larger than the one between Ps3 and 360. The PS3 is smaller than the 360 despite what the pics suggest but the X360 looks a bit better. There's just too much dull space on the ps3. White rev looks fanstic in the pics, can't wait to see it in person.
Oh and FYI, the PS3 controller doesn't look so bad in person though there was a "conceptual design" note next to it.
The thing that irks me about the 360 is the ugly green and the fact that face portion of it looks "cheap". But I still like it better than the PS3.
One final thing, all the next gen consoles look better than their original previous gen counterparts.