I wouldn't say any religion is specifically popular, due to our colonial history Christianity is the more dominant in number but there are so many different denominations that I doubt I could even name them all. There are the old Christian denominations like Catholic, Lutheran and Anglican which a lot of people may identify with because their parents or grandparents were from that particular branch; and then there are the American puritan religions like Mormons, Jehovah's witness, Baptists, Uniting Church etc. those are just a few of the Christian variations.

There are a lot of Atheists and people that just don't really want anything to do with religion. Some actively dislike religious institutions, some dislike particluar religious institutions.

I would probably describe myself as Agnostic, I don't neccessarily believe in any particular deity or pantheon, but I don't deny the possibility that they might exist. I am not a follower of any organised religion but I am incredibly interested in all religions and cultures.

As to other religions, you don't see many openly obvious Jews, I have seen maybe five or six Hesidic Jews fully dressed in four decades and that was all in one particular suburb of Sydney. There are plenty of other Jewish people that just look like everyone else though.

Moderate Hindu, Buddhists and Muslims have lived in Australia for over a hundred and fifty years now and it has only been since 2001 and since Saudi Arabia has started spreading that Wahabbist bullshit that Islam has become a target for ridicule.

As to what role religion plays in the lives of Australians.... It plays absolutely zero role in my life and the lives of my family. I wont claim to speak for others.