So, you want us to get out the super-long-range GT crystal ball, eh? Don't ask much, do you?
If an airline's been around 10 or 20 years and their finances are currently sound, there's no reason why they shouldn't be around in 5 or 10 years' time. This is still an expanding marketplace and, notwithstanding the current economic hiccup, that won't change in the long term. Some airlines may well be taken over by others, but the number of pilots needed will generally continue to rise - but not necessarily in the next 18 months. Don't forget that, like all workers, UK pilots must retire at 65 (55 in BA), so there will always be a demand for replacements.
Keep your eyes on BA, JMC, Britannia, bmi and Virgin to be around in the long term.