Perhaps we can look at a bigger picture of GOLD beyond Australia and its gold mines and beyond the AU/US rate. In a world sense, gold is attractive when currencies loses their value, in this case the US.
The key driver here is not because GOLD is worth more, although it does provide security, hence more demand in these times, hence value go up. But the Big Driver is that Gold is denoted in US dollars, and the US dollars is devaluing fast. I've put together some links to news articles which show this at: http://ozstock.blogspot.com/2011/01/dethroning-us-dollar-part-ii.html
Anyway, US dollar go down, the price of GOLD in US dollar go up. But this is not fair to other countries especially producers like Australia. But rest assured, this imbalance due to currencies will not last long.
In the link above, I have listed an IMF article about plans to replace the US dollar as the World's Reserve currency. When that happens, gold will no longer be in US dollars. In fact, when that happens, the US/AU rate will not be 1.00 or 1.40, if hyperinflation strikes US, get ready for AU$1 to US$100000....