The rest of their plans have been published, too. They start at AUD9.95 per month for 250MB of data (you'll eat through that in no time) and go from there. Note that, in addition to the unlimited plan, customers can get 6GB of data for $100 expiring every 180 days, or 12GB for $150, expiring every 365 days.
The terms and conditions note that you can't use data to make use of peer-to-peer services. It sounds like a good deal for our friends down under. Enjoy your new iPads!
[Via iPad Watcher]