Yeah, it's special for historical reasons, the 444 visa. It's temporary in the sense that it would expire if I left Australia, but I could get another one if I came back. The other downside for any non-citizen is getting deported (or being denied reentry) if the government thinks you are undesirable for any reason.

Edit: and I just want to make clear that I'm not criticising the Australian government in any way with these comments. Please don't deport me.