Nah
Flappie, Aussies everywhere already know what life is really all about!
However, yes, I shall be "back there" early August - check the London Bash thread and hope to see you there!
Sorry that I misunderstood your enquiry, but I think that
reddo has most of the right answers for you now. Indeed, just staying in the same job too long, to which
xetroV alludes, can be a real bad thing. The challenge of learning something new and different appeals to many people and, as reddo points out, there are very different challenges in going from 737 to 747, for example, or even vice versa.
I'd have to say that I've seen many pilots from this part of the world go to other airlines in other parts of the world. The basic reasons have been different in most cases but they all seem to have ended up on bigger aircraft as a result of the move. I think it's in our nature to want to learn something new - and be motivated to do so by the reward of flying something different that goes somewhere different.