Mining boom. There are legions of cashed up FIFO (fly in - fly out) bogans that have more money than sense, and so the price of everything has gone up.
Apart from housing, which saw some years of 30-40% increase in the late noughties, the cost of living hasn't risen much at all - inflation has been reasonably low for a while.
The housing market commentary has been pretty funny. The years of 30% increase had people going "this is pretty good". Now faced with a year of low single digit deflation, the newspapers act like the sky is falling...
I think one reason for this is that rent, especially in shopping centres (malls), had kept pace and didn't drop away even though their tenants were facing tougher competition from abroad. Another is that distributors were less than keen to give up their slice. So, even when some retailers might've wanted to drop prices to compete, they were facing pressure on the cost of floor space as well as product.