Found this info on the A380:
www.airliners.net
"Key design aims include the ability to use existing airport infrastructure with little modifications to the airports, and direct operating costs per seat 15-20% less than those for the 747-400.
With 49% more floor space and only 35% more seating than the previous largest aircraft, Airbus is ensuring wider seats and aisles for more passenger comfort. Using the most advanced technologies, the A380 is also designed to have 10-15% more range, lower fuel burn and emissions