Would the pressure for demand when things get worse in Greece and around the world push the prices higher in AUD also or just USD. I would argue all currencies but a lot of other people I speak to think just USD
All curriencies are being devalued all the time (inflation) to varying degrees. The USD more so, as Spanky Bernanke and his crowd keep firing up the old printing presses. As economies worsen (debt problems, inflation) leading to a loss of faith in the currency, the price of all true monies (gold, silver et al) will rise. In some currencies, more so than others. As available supply of PM's becomes more scarce, the true value of those (not measured in fiat, measured against goods and services) will also rise. The only question is, where will the numbers end up, and what (if any) fiat currencies fall by the wayside along the way. Just my humble, simple little interpretation of the "big picture" mess we're facing at the moment.
All you need to do is look at the long term charts and draw a trend line. Now look at all major currencies and do the same - You will not find any currencies where the trend is down. The trend is your friend