I would think that the economics of going to 380 versus the capex has been run and been found to be not enough to justify proceeding with the new airframes at the present time. Also I think that the 380 loses a lot of it's competitiveness at sectors above 8 hours/
Seems to be a school of thought that fuel prices are king and fuel prices only will dictate fleet choices. While no-doubt fuel prices and aircraft efficiency are important - the other stuff that some people don't think about is
capital cost. New aircraft are extremely expensive (capital intensive) purchases, so with the decreased profits and ability of airlines to fund brand new aircraft (ie. banks not willing to lend money) that introduces other commercial considerations.
It is a bit of a chicken and egg argument about the most profitable airlines having the youngest and most efficient fleet, and less profitable airlines often having older and less efficient fleets. Add in government distortions like different tax and depreciation schedules, government ownership and stuff like Ch.11 Bankruptcy and its very hard to measure apples with apples.
Agree with some of the comments that A380's are excellent "hub-buster" or slot constrained aircraft, but once you start thinking about direct point to point traffic without slot constraints then the A330 A350 and B777 start to make sense. Its been interesting that frequency rather than a few large flights a week has been an area of competition between airlines, with older widebody services often replaced by more frequent narrowbody services.
Also interesting to see that although fuel prices are important - the growth of more narrowbodies with more frequencies has told us an economic lesson in the value of labour - particularly flight crews. You only have to read about some of the salaries in the US airlines (down to US$16K pa) and the surplus of pilots to see interesting market forces at work. But labour costs are still trivial but becoming more globalized, although there is no doubt that cabin crew costs between say SE asian crew and Australian crew would be noticeble.
I have heard that the new B747-8 is fairly cost competative to other long range aircraft - especially if you could pick them up cheap. If you knew that fuel prices were going to drop or Airbus were to go broke and/or the airline market grow quickly, a very contrarian and bullish sentiment at the moment, then you would do well buying up a big part of the B747-8 production line now...
