I am one of those that "lurks" and doesn't post much. I like to click through the different rooms to see what's new. In my opinion, a lot of the posts don't warrant a comment. For instance-someone posts about what they did today...that's nice...does it need a comment from me? Or someone posts about someone else doing something...again, that's nice...does it need a comment from me? Or someone posts a link to a video...I'll watch it...does it need to be commented on by me?
I guess my point is-If I find the post relevant and I have a relevant reply, I'll post it. I'm not going to post just to "up" my post count like it appears some do with their replies. I'm not going to post just to post. If I have something to add, I'll add it. If I don't have anything to add to make the thread more interesting or if I have no opinion either way in regards to a thread, I won't post.
One thing to keep in mind-Even though people are "lurking" and not posting, they are still visiting this site. They may not post but RealTree hasn't lost them completely.