Crowd control- with parts of the Mariott under construction, some people here are saying it gets out of hands at times.
(Note: sorry you'll have to cut and paste for now. This software won't let me link it for some reason.)
Keep in mind there are a LOT of people here. Waiting for the elevator takes epic lengths of time and people are wearing big, bulky costumes. Last night we went to the High Velocity bar in the Mariott, where light sabers were as common as brightly-colored cock-tails.