This is why Glo stated the fuel burn per kg on these long sectors is the same for the 777 and the 380
Don,
A quick look at SFO v LAX yesterday- distance within 200NM of each other.
The 777 to SFO had an available payload of 41T for a fuel burn of 124T, so pretty much exactly 3T of fuel to shift 1T of pax or freight.
The 380 to LAX had an available load of 56T for a burn of 201T-3.6T/T of payload- so 20% more per unit.
So it will depend on how much revenue you get for that extra lift v cost of fuel.
A major rise in fuel cost (did someone say Iraq?) will SERIOUSLY effect the 380s efficiency- and THAT'S before we get the 777-8/-9.