Why does it matter if it's 1/500? Is that functionally any different from 1/250? It seems like the recycle time of the lights shooting full power at 8fps is more impressive than syncing at 1/500...Don't the new pocket wizards have that built in? (supposedly you can get one extra stop of sync speed they claim)
It's impressive because the new PW transmitters don't work well. He managed to get his to work consistently somehow. 1/500 instead of 1/250 means one stop less ambient and less chance of motion blur in shots like this.
8fps RAW on the camera & lights just means expensive gear.