Ning has a new feature--the ability to create categories for forum discussions. When you post a new discussion, you have the option of choosing a category. I believe I have to create the categories--and, unfortunately, put past posts into the appropriate categories! (That won't happen overnight...)
I created a couple of categories already. One is "Introductions," and while I only expect one original post there, I think it makes sense. I also created "Help Needed" for when you are asking for help or feedback, and "Site Features Discussion" to talk about this site and how we can improve it. There is also a "Site Announcements" category (which I'm using right now), that only I can post to (although anyone can reply/comment on). You'll need to reply here and let me know what other categories you want.
The value, I believe, of the categories is that you can subscribe to the RSS feed just of certain categories, if you like. It doesn't appear to affect the way the discussions appear on the front page, but if you look at them under the Forum page, you will see that they separate out.
Let me know what you think.