Hi @Matt Riley. I'm a fellow Australian who lives in Atlanta. I didn't move here for real estate - we were transferred with my husband's work. I still see potential in the Atlanta market although it has rebounded a lot since the recession so don't expect to clean up with rock bottom prices.
I would make sure that you are investing in an area of the US which has strong employment and growth. I like Atlanta's prospects for growth because it has large companies based here already (Delta, Coca-Cola) plus new ones moving in. Mercedes just announced they are moving their US HQ down to Atlanta. Plus there's an Australian club! Because it's on the east coast it does take longer to get to Australia so if this is a big factor for you then you'd be better off being based on the west coast (although Qantas does direct flights from Dallas to Sydney).
Have you been on the Somersoft website in Australia? There's a section there which covers Aussies investing in US real estate. It could be worth trying to connect with others who have already bought property here.
PM me if you need any more info.