Thank goodness — someone forgot to charge the Australia tax. Microsoft just issued a statement confirming that Australians who buy a computer running Windows 7 over the next six months will pay just $14.99 to upgrade it to Windows 8 Pro — the same deal that's running in the US.
The offer applies to PCs purchased between June 2, 2012 and January 31, 2013 (and the upgrade has to be purchased before the end of February 2013). The offer applies to Windows 8 Home Basic, Home Premium, Home Professional or Ultimate. That's more or less everything on the market, save for ultra-cheap netbooks running Windows 7 Starter. But those are a rare sight these days and can't really run Windows 8 anyway.
You won't be able to redeem the offer until the release version comes out, and we don't yet know what the final price for a standard upgrade will be. But at least you're getting the Pro version, which makes it a little easier to upgrade to Media Center if you wish, though you'll still pay an as-yet-unspecified amount extra for that privilege.