Back in 1991, the Golf Magazine list had:
Royal Melbourne 6
Kingston Heath 28
NSW 58
Royal Adelaide 53
Victoria 84
Commonwealth 82
Australian 96
Apparantly at that time Metropolitan 'hadn't been discovered'.
I suppose it proves that despite Australia having lots of high-quality courses, particularly on the sandbelt, very few of them are what could be called "world-class". Generally they're fun courses to play, and on the local scene are considered excellent, but do they stand up when considered alongside the world's elite? Except for RM, it seems not.