RevMan
That's interesting.
I've seen different coloured signs over the scanning machines (Red, Blue and Green), but not dedicated use - everyone mixes regardless of the ticket class. But as said before, the queues move very quickly and it is a non event normally.
Not sure what concourse though, so I'll look out for A when I travel.
The main objection I have at the BAA airports is that they generally don't have enough channels open and seem to think it is okay for people to have to wait for a long time.