Australia is actually pretty dull to live in. Nice for a couple of years but once you've got over the novelty of Xmas day on the beach and such like you can start feeling trapped. The problem is that it's just so damn big, very hard to go anywhere interesting for just the weekend.
Perfect place for bringing up kids though, i'd imagine.
A mate of mine moved there a few years ago, with work. Was nominally a two year deal, with the option to stay (and loads of amazing financial perks) on after.
He has moved back to the British Isles (now lives in Dublin). He said that living in Aus was ok at firtst, but after a while he and his missus just felt increasingly isolated, and that they were in a really 'sterile' culture. Nothing felt quote 'real' for them. As for the bringing up kids thing; he said that he wanted his kids to grow up in a place where they'd actually mix with other cultures more, as he'd done, and that where they were just din't feel like that was all that readily achievable (and I think they were in Sydney too).
He also said it was the little things, like a simple 'phone call taking on a new dimension, that got to them, and just feeling really cut off from the rest of the World (we can nip across to Yerp in just an hour or two).
I'm sure many people love it out there though. and I also know Aussies here in London who are adamant they will never go back to live there, as they prefer it so much over here.
Courses for horses, innit?