There will be a lot of misinformation flying around on social media because the guy was yelling "Allah Akbar"- please don't repeat this misinformation until the police have had time to investigate it. A Couple of things regarding misinformation and confirmed facts:
1. NSW Police have confirmed that the man was known to them and had known mental health issues. He was apparently known to be carrying around material on mass shootings, and was found with a USB in his pocket, but no word yet on the contents.
2. There are unconfirmed reports suggesting he was actually a mental patient until a few days ago.
3. NSW Police are not treating this as a terror incident. The person was not on any terror watch lists.
4. The man was caught on video shouting "Allah Akbar" but it is unclear whether he was Muslim. He was also caught on video shouting "Shoot me" so there is some suggestion he might have just been yelling that to incite the police to shoot him.
Please remember - it was only a few years ago that we actually did have a lone wolf terrorist attack in the city by someone who was indeed yelling "Allah Akbar", so if the NSW police say this incident has nothing to do with terrorism then I believe them.
One other thing - while this event is absolutely awful, and a woman is dead, to me this is an example of gun control in action. In America this guy would almost certainly have been able to obtain a firearm in some states. In Australia, given his mental history and monitoring by the police, he would have been ruled out immediately by any background check. Because he didn't have a firearm, some good samaritans were able to overpower him with some chairs and milk crates.
It's a lot easy to be a "good guy" when you don't have to have a gun.