At the end of the day, the Irish economy popped because too much of the banking sector was propped up by loans which required housing prices to keep going up, and never ever go down.
What part of that doesn't apply in Australia?
Yes, APRA is finally stepping in and reining in the banks, forcing them to be stricter about new loans and to hold more reserves. But the banks are fighting those regulations tooth-and-nail, and will continue to do so.
We also don't have a clue how exposed our banks our to the shadow finance economy, which is what caused the GFC crash in the first place.
All we do know is that the only reason the banks didn't crash in early 2008 was because the Australian Federal Reserve and the Rudd Government stepped in and guaranteed the banks - in a currency we had control over (unlike in Ireland, Spain and Portugal). Apparently we came within 30 days of all of the Big 4 closing their doors - that's a lot of risk.
Mind you, that's why I don't think a complete crash, on the scale of Ireland, Spain or Portugal, will happen here - the government will always step in to prevent it. The question is how much that will cost, and how much of the money gets diverted to line the pockets of bank executives and shareholders in the process