I bet the breakeven number for the A380 has at least doubled. Airbus orginally claimed they'd break even with 250 airframes. I bet now it's at least 500. Boeing didn't get up to 500 deliveries of 747's till 1981 which was twelve years after the first deliveries with no competitor in its class. Boeing didn't get up to 1,000 deliveries of 747's till 1993 twenty four years after the first deliveries. By the time the 747-400 production is finished about half of all the 747's ever built will be the 400 series.
After Boeing finishes the 787, they will surely build a composite replacement for the 737 AN 757 using technologies derived from the 787 program. After that program Boeing will be ready to tackle a replacement for the 777-300ER and the various 747 models still in service using 787 based technologies. Boeing could cut the legs from under the A380 program by announcing that program in 10-15 years. A large twin engined plane big enough to replace the 747-400 and 747-8 would be so much more efficient than the quad-engined 747's and A380's that it would kill off new A380 orders. If Boeing offered a cargo version of this plane with a swinging tail door to allow loading of oversized freight, there would be absolutely no reason to continue even the freight version of the 747. The A380 would have to be terminated without ever producing the high profits Airbus promised.
As per my friend, AT LEAST DOUBLED. Your analysis is exactly what he said, and he is in a position to know.