I was flying on flt. 1310 from las to lax (yesterday) 9/17/12--scheduled departure time 11:20 am.
The boards showed that the inbound flight was going to be 20 minutes late (now 10:40 am instead of 10:20 am). The inbound sat on the tarmac 5 minutes waiting for an agent to operate the ramp equipment. Even after the pax deplaned, a GA did not appear until close to 11:00 am (instead of T-1 hour of 10:20 am)--she was wearing a yellow "managers" vest. A second agent appeared at 11:05 am.
[The line of pax needing GA assistance had grown to over 10 people by 11:00 am]
Overall (as a LAS flyer), I would say they are staffed adequate....I will say I had to check a bag on 2 trips and waited 20 minutes for the bag....in the eve 9right around the red-eye departures and mid afternoon waited no more than 10 minutes....YMMV...
Usually, without a checked bag, I am from the airplane blocking in to my car in 10 minutes....