Do this tomorrow, first thing in the morning, call in sick to school/uni/work whatever, process the photo first, go get a passport application form, fill it in, get the photos, make a back up in iPhoto, get a family friend, not member to verify the application and send it in. Then hope and pray that the new passport comes back in time.
With a bit of luck and trust in Australia Post, it might make it...
Or you can get a refund for that holiday...