I was eventually going to start my own thread on when is best time to visit Down Under, but I guess I'll just piggyback on this one. I like the sun and warmth, so I definitely won't visit in the winter (North America's summer). When I visit, I intend to go to Sydney and then to the Gold Coast for the beaches and some scuba diving. I've heard warnings about deadly (box?) jellyfish. When should I go, and is it worth scheduling my trip to avoid jellyfish season?