Somersoft has a very wide readership. I've found there's a huge number of people who regularly read the forums and never write a single post, which is fine. Despite the large number of readers, the total number of property investors in Australia is substantially larger so you certainly can't qualify a service provider or property investor based on their exposure to this site.
There's also a large number of people who have heard of Somersoft. They've read a few posts but ultimately decided that they're forging their own path, or they're not interested in sharing their experiences via this type of medium. I think most of my top 10 clients have heard of Somersoft but few of them are regular contributors. I've also told a few property professionals about Somersoft. The forum would likely greatly benefit from their expertise and I'm sure they'd generate loads of business in return, yet they don't feel comfortable contributing.
There's also loads of ex contributors out there who no longer post. see_change mentioned Dale GG, Nick M, sim , goanna , ruby, mark b, Rixter, Jacques, michael g, yuck, The Wife, Micheal Croft. All have been amazing contributors at one time or another (look up some old posts). Most haven't contributed in years.
You definitely can't judge people if they don't contribute here. Instead use the forum to gain a basis of understanding property investing. You'll then be in a better position to judge the quality of the information you do receive and to debate the ideas with them.
There's also no reason why you can't organize a meeting of Somersoft people in TAS. I know there's quite a few people residing in TAS who contribute or lurk on the forums. Just organize a time and place at a restruant then put a post in the meeting point section. The worst thing that can happen is that you'll go out to dinner one night.