Yup, 457 working visa allows you to stay as long as 4 years max. But it is also changed that time when I got mine, I only got 2 years visa, and now my company is helping me to revise the visa, extending for another 2-4 years stay.

I'm in the O&G industry, as a geophysicist. I think my company is in need of people that time, hence I got the offer to base permanent in Australia.
O&G and mining industry are strong in Australia, so I think there's a good chance to land a job if you're engineer or somewhat related profession.

As for mercury, it may be a possiblity that he obtained PR during his 3 years of study in Australia.
I only heard from friends, so dont take my word for it, but isn't it the eligbilty for PR is only 2 full years stay in Australia? Of course you need to pass their exams and fulfill certain criteria before granted PR.

I'm actually interested to see extremepower replies, so there're Malaysian community in Melbourne and Sydney that play badminton. Cool.
I'm currently in Brisbane by the way, any chance there's a similar group at here?