That's kind of surprising. How much do international students pay over there? I know lots of Canadian students who look at US schools and just decide they can't afford it. Tuition costs are usually a good 10x what they would be in Canada =/ We get the "local" rate no matter where we live in the country here unlike the US which I think does it by state.
A bunch. It costs a bunch.
The typical 3 year degree for a domestic student costs between 18-30k AUD. 6000 p.a. for Arts/Education/Nursing, 8000 p.a. for other things (normally, Science and Engineering go here, but there's a scientist shortage at the moment so I think it's on a specia cost bracket, else it's in the Arts category), 12000 p.a. for Law, Medicine.
However, those costs are because the Federal Government subsidises domestic students, along with a special no-interest index-linked loan program that's paid back through taxation (provided you're earning over a minimum threshold of 30k p.a., if you're below that you don't have to pay it back until you are); the premise being that going to university means you will get a higher-paid job and hence will eventually pay more tax and cost less in welfare.
Because International students don't have the incentive to stay and pay tax here, they don't get that benefit (nor do they get travel concessions etc.) and so the University can bill them whatever they want. I think the typical cost then is $20k-$25k p.a. for a total of $60k-$80k. And that's not including the living expenses or rent (which typically needs to be on-campus since they can't travel cheaply, and on or near campus accomodation is really pricy due to high demand).
Now, one of the reasons why the University would be motivated to market more to International students is that because of political campaigning from the left-wing student lobby, the Federal government forced all universities in Australia to abolish domestic full-fee courses (i.e. they would run a degree without subsidising, so $20k p.a., that was exactly the same as a subsidised one; thus people had a second chance to get into the university if they were willing to pay more for it. The same loan program as above still applied, however, so actual payment can be deferred to tax; I used this to get into the Combined Law program before I transferred into the subsidised one.). If they refused to do so, the Government would not subsidise any of their courses.
Consequently, the university could not take on any more domestic full-fee students, so to replace the income they obtained from them, they started recruiting more International students who still pay full-fees.
However, as you said, I'm surprised we've had such an increase given the large comparitive costs for a Canadian student to study there or study here.