kmack- Love those photos of the Cliffs! When we were there everyone was climbing over the walls, as well. I wasn't interested in doing that, but it seemed to be somewhat the norm. We went towards the south end of the Cliffs, along that little dirt trail. There's a sign saying you shouldn't go, but it's perfectly safe and not at all close the edge. Everyone was walking out there, too.
My DH goofing with the sign at the head of the trail:
You can see people out the ledges in this photo:
Funny thing is that in traveling around the country we ran into so many tourists who'd been to the Cliffs prior to those walls going up and they were all lamenting how ugly and unnecessary they were. I guess it's easy enough to climb right over them, so what are those walls really accomplishing?