Communication (between members) is the most important part of a community, but it’s not the only part. Don’t stop at a simple forum. Push your technology further.
There are many directions you can go in.
1) Add a blog or main news page. Write about what members are doing. Feature contributions from members. Do roundups of the sector. Highlight what’s going on. This is your local newspaper.
2) Reviews and ratings. Add ratings and reviews of the top product vendors. Let members add their reviews. Host awards for the highest rated.
3) Document / wiki. Document the collective wisdom of the group. Create the definitive database for the sector. Have guides for newcomers, experts, and people tackling the most common problems. This works really well if the community is based around a product.
4) Organize events. Online or offline. Create your own events. Host interviews with experts. Better, let members organize their own events. Let them host their own interviews too.
5) Ratings. Create a reputation system. Make it easier for the top members to stand out.
6) Add courses. Develop learning or training modules people can progress through. This raises the quality of discussion.
Most community platforms enable you to do all of the above. If you are on an open source platform, you can add features when you need them at little cost.
Two common mistakes here. The first is stopping once the forum is going. This leaves a pile of potential on the table. The second is trying to implement all of the above at once (especially from the beginning). You need a lively hub of activity before you can add the above.
Once the forum is going, start pushing your technology a little further.