Well I have lived in both and I would say Melbourne. The roads are better organised, it doesn't sprawl quite as much and the sporting events are arguably better, and the cost of living isn't quite as high. Having said that, it depends a lot on what you are into. Sydney has the harbour which is a fantastic spectacle for water sports and boating, and I think Sydney's beaches are nicer. It also depends on which are of each city you live to, as this will determine access to a lot of the available activities. Both cities have reasonable, but not fantastic, public transport (although I don't regard either as terribly safe). I must say Sydney's public transport is the only one I was ever offered to buy drugs on, and I've been on it much less than Melbourne. Mind you the drug dealer was a lot more friendly than some of the trash that rides Melbourne's trains
In regards to TT, I didn't play when I lived in Sydney, but I think it may be about equal in terms of availabilty. Not quite sure.
All in all, I prefer Melbourne, but then I have spent more time in Melbourne than Sydney so it may bias my thoughts. It would be interesting to hear the thoughts of others. Personally, if I could live anywhere in Australia, it wouldn't be Melbourne or Sydney. It would probably be a country area not prone to flooding or bushfire