It's a balancing game... On the one hand we don't want a bunch of dead sections, on the other hand, as J.R. points out, it's nice to have focused discussion groups (keep me away from the forced induction section - if Frankn7 doesn't kill me by then, my wife will).
Mike, do you use the bottom right hand of the home page? It always lists the 10 most recent posts, regardless of section. That's where I go when I come to the site.
Also, if you are interested in a particular area, but don't want to click there regularly, you can subscribe to that section and get an email whenever there is a new post.