Well, I know I'd take Australia over the United States. I hunch that New Zealand would be another choice. Those and Canada might possibly be my only choices above the USA.
I'm still "hung" on where to place UK among preferences - I know I'd AT LEAST love to live there, but I understand that economic opportunities may be more limited, and likely I couldn't have built THIS job there from the ground-up as I have here, the UK economy generally isn't doing that great, etc.
There's something marvelous (to me) about being in a country that speaks English, too. It's my mother tongue, but I also think it's the most "fun" language in the world - is there any other language that is such a melting pot? Because the history of English vocabulary comes from so many world sources, there is a hell of a lot of FUN to be had with it: puns, contradictions, riddles, subtle nuances, etc. Those who know me, know that I LOVE language, grammar, etc.
I can only reasonably begin to compare with Spanish. I've often noted that Spanish might have one word for something, and English might have four or five words for the same thing (with slightly different feel to each word), and sometimes Spanish can be more diverse for an idea or concept, but it seems often English has borrowed similar words, for the same thing, from two or more different languages.
If I was brought up in a country that didn't speak English, though, I would probably never know English WELL ENOUGH to realize the hidden delights of this language. Yeah, like I definitely am fond of Italy, and was pretty darn impressed with Buenos Aires (.ar), Hamburg, Zagreb (Croatia)...but during my lifetime ALL of those places have been through some horrific and wrenching times, and the Italian government currently is not THAT stable...
Canada has generally been NEUTRAL in wars, and hasn't seen a war on its territory in a very long time, and that counts for a lot too.