Flew out of South Terminal on Thursday aft. Aircraft on stand 1 hour before departure time. Called to gate 50 mins before departure time. Stood in corridor waiting for gate agent who arrived 25 mins before departure time. Made mistake logging into system or system problem (never explained) and then did a manual board using one person only, boarding started 10 mins before departure time at a painfully slow rate, boarding direct to aircraft took nearly 45 mins. Departure delayed consequently. Air crew furious. It really is now operating as a slick shopping and leisure centre with some pesky planes parked up round the back. However I do have to commend security which was busy yet slick and efficient.