The A380 program has already secured 6 years of production, so I don't fully agree with you.
The A388 will not represent the real future of the A380, it will become more evident with the A389 that's planned to EIS by 2017.
Airlines will tend to concentrate on hub to hub traffic in the future as we can see with the big majors reaching for big planes.
What will eventually compete very strongly with aviation is the projected Maglev line to EIS in France in 2011.
Such a Maglev line could represent a threat to short haul travelling though being a great solution for the environment issues.