Working for an airline that operates both types and has additional orders for both types I have a little insight on this topic. Watch very carefully what both Emirates and Singapore do over the next year or two in regards to firming up options and/or placing additional orders for Boeing 777s versus the possible cancellation of orders for the Airbus 340. Head to head the 777 destroys the 340 in almost all aspects except purchase price. While it wouldn't be prudent to post how much money we lose per week on our A340-500 service to JFK, it is known that the 777-300ER will take it over when they arrive and is projected to be profitable on the route. On a typical long range mission the 777 will do it 30 minutes faster and carry 10,000+ lbs. more payload while burning 20,000 fewer lbs. of fuel. On a daily basis that adds up to big savings over the initial purchase price difference. These economics are what make the 777 a superior aircraft.
In a recent Flight International article on the subject, Tim Clark, the President of Emirates pretty much said that we are reevaluating the 777-200LR as a possible fleet type. Reading between the lines, what it really says is the A340-500 is a piece of junk and we will most likely opt for the 777-200LR over any additional A340-500s. It wouldn't surprise me at all to see our 20 aircraft order for the A340-600 silently disappear and be replaced by additonal 777-300ERs. You will very likely see a similar situation at Singapore where it is well known they are not happy with the A340-500 and will probably get 777-200LRs to replace it. They are also replacing a majority of their 747-400s with the 777-300ER over the next few years.
Typhoonpilot