PenultimateHop:nitrotech: You could still run telstra as they have 2100 in all metro areas - just in the sticks you won't have any coverage.
Telstra's 2100 coverage in Melbourne is pretty good, and outside of the 2100 coverage you will fall back to EDGE on their GSM900/1800 network - which is quite a bit better than "no coverage" ;).
Very true I was talking about WCDMA as the OP was asking about mobile broadband, as much as GPRS and EDGE were good a few years back it's hardly broadband by todays standards.