.I think Aussie is wrong, there is now a small campus in Brisbane (so you were right).
I live in Brisbane and its okay, I have never been to Melbourne but, a lot of my friends have said that is is 10 times more busier than Brisbane and a lot colder too.(even though that doesn't bother you, but Brisbane generally has great weather)
Brisbane is closer to a lot of places, like the Gold Coast (which I love - use to live there) which has many tourist attractions, theme parks, nice beaches, national parks etc Brisbane also has some like the Modern Art Gallery, Museum etc.
Both Brisbane and Melbourne have great nightlife (so I have heard in Melbourne) and education, economy, food, friendliness and hospitality wise would pretty much be the same/similar. Outdoor activities would probably be better in Brisbane as if it close to most things (side note: you can go scuba diving in Morton Bay, Stradbroke Island).
I don't really know if I have helped but, hopefully is has assist you in making up your mind. Just remember Australia is a little different to the states, a large majority of people are starting uni now (February/March) however, there is mid year intake just less people start then (June/July).