You now have 2,860 users which is not bad.

It all depends on a few things.

Without sounding too wanky, I have been in online business for seven years now so I like to think I know what Im talking about but... then again. I do have a picture of santa's little helper as my avatar. Lol.

It all depends on what type of venture this is. If this is a for profit site then there are certainly a few things you could do to get more registered and active users.

From my research I understand that many in this industry are not active online users. There is virtually not much difference from your forum to others, so its not as if some forums have thousands and thousands of users and you are the only one missing out, people in this industry are just not that active online.

What I would be doing is:
-placing paper ads in the several offline popular papers and form guides. Lots of race people there that are currently not active online. They can be converted easily.

-injecting a lot more social into the forum (facebook, pinterest, twitter etc). Once people sign up they should be offered links to share and like the forum. Because you use Vbulletein there should be some easy plug ins on their API. I noticed they just released an app...

-create video campaigns on a branded youtube channel, make sure you target aussies with proper keyword tags (get the videos made for cheap at fiverr)

-try focus your paid ads more on local advertisers. There are plenty of VET's, trainers, breeders, food suppliers etc that want to do more online but dont know where to go for exposure. Offer them a week free (or whatever you can afford) in exchange for them emailing their list for you and asking their partners, clients to get involved in the forum.

-SEO, Vbulletein has some awesome offers for SEO. The reason I say this is because I noticed not too many threads appear in search results. MOst people wont search for "Racing forums" they will find the site via search results and then get involved that way.

-Have a popup prompting people to join after a few seconds on the site as an unregistered IP.

-Stay active in other popular online forums and learn from other Internet Marketers. There are two very popular Internet Marketing forums, Im part of both and they have been paramount to my learning over the years... they have also been paramount to many late nights on the beers... lol

-Branding. I notice there is no branding on this site, no logo etc. If you want people to tell their mates about the site and share it you need to build a good brand

-"Whats in it for me?" This is what any person looking at the site is thinking. For anyone to use the forum they have to have a payback. Whether its getting an answer to a question, having the pleasure of sharing their experience, contributing or having some sort of commercial interest invested into the site. They want to know whats in it for them.

I think it's good that you are vocal about wanting to expand and grow, most people are too shy to be open about something like this.

Ill assume you do this part time or casually after hours? If so you need to automate as much as possible which should be easy off/on option in your management area. I noticed my account had to be manually approved and so do any links posted in threads. This time could be better used to grow the forum.

My 2cents, cheers.

__________________