The other main Australian concentrated discussion board that has a wealth of information about cacti and other plants is the Coroboree from Shaman-Australis. I've signed up twice and am still waiting on validation.
This board is great but the Coroboree seems more active and I'd love to participate, especially in their seed buy/sell/trade section.
If any of you guys know how to get validated there, plz let me know. thanks.