While in Sydney, I noticed that free wifi wasn't that common. Some places did have it, a few others had an anonymous named wifi that you could get the password for if you knew to ask, and quite a few had paid-for wifi.
I'm now up in Brisbane, and I'm wondering if it'll be a similar thing. Is free wifi more common here? Either municipal provided, or from cafes etc? Or is it much the same as in Sydney?
Brisbane seems a bit more enlightened on the free wifi front - the council provide free wifi in 22 parks!
The wifi in parks page includes a map of the parks with wifi, and where in the park you can find the hotspot (if the whole park / square isn't covered).
Not sure about cafes / shopping centres etc, but if you can go and sit under a tree in the city centre and get online, it doesn't matter so much!