Bitcoin is just taking off in Australia, getting a lot of media attention now. Setting up the pool to AU users would explode.
This.
It seems you're caught by the Bitcoin hype and forget to calculate your venture through. The difficulty is claimbing rapidly and at this point its easy to say that unless you have a strong ASIC provider and very cheap energy, you won't make your investment back.
I would explore the option of running a pool in Australia if there is no significant one yet.