Okay, I'm doing it Down Under next week in Sydney. What do I need to see besides the obvious?
The Royal Botanic Gardens are very nice if you feel like wandering around a park for a while(find the bats/flying foxes at dusk! Aussies... is there a difference?). The Sydney Aquarium is pretty great. I'm still kicking myself for taking photos of the fountain from the Matrix("freeze it!") and not realizing it was the same fountain until I got home. Would have had some cooler framed shots of it otherwise(I can't remember if it was in Strand Arcade or not). Walking under the Harbour Bridge is pretty great too due to it's sheer size.
Avoid the rum(tastes may vary).
And take one of the touristy boat rides.