>That would be nice for different people who have "XYZ" ARBNs  registered in
>different states. If it was starting from scratch you could then reserve
>.com.au for ACNs only. But then there's the issue of companies trading under
>their ARBN and not their company name.
>
>(hmm, i think i've come full circle now)

No you haven't!  A company can either trade under its name as registered
with the ASIC, or that name and a business name registered under the
business name laws of a particular State.

Thus,  XYZ Pty Ltd could have the domain name xyz.com.au  and  also
trade in say QLD as "Business Name" and register the domain
businessname.qld.au  If it were to trade under the business name in another
State, it would need to ALSO register that business name in each State where
it intended to trade.  Consequently, it could have the domain names:

businessname.qld.au
businessname.sa.au
etc.