It’s a day early but you can now activate your Zune Music Pass in Australia by visiting http://www.zune.net/en-us/products/zunepass/default.htm and logging in with your Australian-based Windows Live ID. You can sign up for the 14 day free trial after which your credit card will be debited $11.99 on a monthly basis (or you can switch to the annual subscription for $119.90 to get a saving of two months subscription).
The link I have provided is for the USA but it will recognise that you are in Australia and offer up the correct pricing (the USA get US$9.99 a month or US$99.90 for annual subscription). You an see that the Australian prices are correctly reflected below.
I have also verified that Zune works fine after you have enabled your trial (you might need to close and reopen it so it can query the mothership about your Zune Music Pass status. If all is good, the prices for songs should disappear and you should see the option to download songs and you can stream them straight from the interface.
I just need to work out how to make my Samsung Omnia 7 running Windows Phone 7 aware of the Zune Pass and I’m set!