Linguists have been rushing around the US trying to document last speakers of various languages, and I'm sure they're doing the same thing in Australia. I heard a story of a Native American language, and the last speaker was a woman with no teeth, so they don't actually know what that language sounds like, because they only have recordings of her.

It's sad when languages die, although practical concerns often lead them to. It is quite common when the older generation suddenly realizes they are the last speakers of their language they will make a concerted effort to revive it in younger people. Sometimes it even works. I heard a story of a Native American group who now have a population of old people who know the language, young people who don't, and then children who know it again. It skipped a generation as the older people went to the little children and had a program to teach them the language.

A language is a very strong embodiment of a culture, especially for a minority group speaking a minority language. A bit of the culture is lost when they loose a language and that is sad, but it happens. What drives me crazy is when one culture sets out to ruin someone else, and purposefully takes away their language. It happened in the past to the native people in both America and Australia. Children were taken away from their parents and put into schools where they were punished for speaking their native languages. That's not what has caused the natives languages to die out, but it certainly speeded the process up quite a lot.

Sorry for going on about it, I'm a linguist, and this is something I feel passionate about.