"Everybody is looking for the first signs that overseas investors have had enough," one banking analyst said.
Gerard Fitzpatrick, global fixed income portfolio manager for Russell Investments, said he was increasingly cautious about lending to Australian banks.
Speaking from London last week, he cited the recent catastrophe in Ireland, where the house price bubble effectively broke the banks.
"I'm not saying Australia is the same as Ireland, but there are definitely similarities," Mr Fitzpatrick said.
"You've had a booming housing sector and rapidly increased lending by banks.
"The two situations have enough in common for bond investors to consider the consequences for the Australian housing market - and the banks that are supporting it."
Be aware that this is "financial pornography". It is also possible that the author of the statements has an interest in seeing the Australian dollar decline in value.
Be aware that if the banker boyz in New York and London see an opportunity to short the Oz dollar and then talk its value down, they will take it in a heartbeat. This is a game to them and it makes them hundreds of millions of dollars if they can get it right.