Nigel where would you rather be, USA or Australia or is that a stupid question to ask.
I enjoy the option of being able to live and work in both countries. They both have their pros and cons, but it comes down to where I have a job and can make a comfortable living. It was my job that brought me to California over 20 years ago and life here has been good to me, though the economy everywhere is pretty much down at the moment.
Because I work in the video games industry I have more choices in the USA. In fact I work with a lot of English computer programmers who moved here for the same reasons. Life in both countries is great and I really value what they both have to offer.
My sister is a graphic designer and she moved overseas for her job as well ... and now lives in Tunbridge Wells in England. The world is very small nowadays.