We just got our visas. I say we as in my wife (I'm Australian) and I say visas because we applied for 2 in the end. She got approved both the 600 and 651 visa.
The reason we got it was because she applied for a cancellation of the 651 application after waiting 45 days. It then mysteriously vanished from her immi account. We called several times and finally got someone who actually seemed like they cared and tried to help. He recommended we cancel the cancellation as this would take up to a month and processed this request for us. This meant that someone looked at her account that same day and just processed everything.
We're so happy. After 50 days, 4 different flight and hire car bookings and a lot of stress, we can finally return home and introduce our 18 month old boy to his Australian family.