Just following on from Kegs post (first post was great but next time tell us how you really feel about it).
Cat II/III is not only about the LLZ/GS beams having triple uninteruptable power supplies, triple transmitters, triple antenna etc, but also the lighting requirements are to a higher standard, ie approach lighting leading into the touchdown zone, runway and taxiway centreline lighting is closer together etc. Airservices Oz seem to be holding off on Cat III ILS istallations as they hope that development of Cat III capable augmented GPS approaches will save them a heap of money. They will still have to spend money on the lighting systems so they should be fitting that now. It would make it a lot safer in situations like the A330 in Perth.