OK I've just done a quick calculation - based on HKD prices, the Model S is about $2k less expensive than I was previously expecting. However, that is probably due to exchange rates - so I'm thinking that eventual pricing will be very similar.
$97,650 if calculated based on current spot rate from HKD conversion; $95k announced on Gizmodo.
Edit: Also, top of the line fully optioned P85+ is $200k according to Gizmodo, and on a pure mathematical basis, conversion from HKD is $190,575, which means that Australia is $9k more.
Still, I guess that's as low an "Australian tax" as we'll ever get on a motor vehicle.