All the nightclubs and pubs are situated in the city central and 'the valley'. The Family and The Monastary for electronic music, the press club is a nice loungy bar (easy to pickup here on a busy night) and is next door to the empire which isnt a bad bar.
Not sure of your age or interests, but if your looking for a place to do cold approaches i reccomend the city, QUT and UQ (unis) are within an easy walking distance.. generally more girls than you can poke a stick at.