Those surveys are bullcrap, everyone has a different experience. Honestly I find Australia to be BORING. I like traveling, and like going to places like South America and Europe, two destinations which are too expensive to go to from Australia. A bargain roundtrip to Europe is around $1500AUD, I could get bargain tickets to Europe from the US as low as $300AUD.
I am from Miami, I have spent a lot of time on the West Coast, and yes I have seen quite a few Aussies in both Miami and in Cali, and no I did not mistake them for being British. There are tons of famous examples of Aussies who have moved to the USA. Even the Crocodile Dundee actor won't set foot in Australia again, how ironic.
The Mercer surveys are nonsense, they pick the most boring places in the world as the best places to live. Life is really what you make of it. Frankly speaking I saw another survey, a survey of cities with the world's best looking women, cities like Copenhagen, Montreal, Barcelona, Moscow, Prague, and Stockholm ranked very high. That is a survey I respect.
I have been to Moscow, I have to say wawaweeewa!!!
Sydney was way down on the bottom of that list, its not surprising since so many Aussie guys go overseas for fun, if you know what I mean, and the fact that every other guy here has a mail order bride or girlfriend.