I always get a kick out of the Premium Checkin at OOL. All the platinums police it, when you walk down it, people give you a little glance and if you don't look like you belong (Easy to pick, because you'll be holding a surfboard or wearing board shorts.) somebody will kindly point you to the right place. If you sit back and watch it's quite funny to see the whole thing happening!
I've noticed the Premium line in Brisbane is a little hidden, so most don't end up in it. However, Melbourne one, in my experience is pretty average and isn't policed at all.
I recently got a few of those "We want your feedback about your recent flight" emails from Virgin, I noted in there the woes about Priority Security lanes. Personally I'd like to see a staff member policing it, but if that's not feasible, training security staff to police it a little.