Mostly driven by internet searches, I think Brent has the site optimized for Google hits, or at least just below the paying sites. With over a decade of threads there are a lot of chances for keyword hits. These searchers are often looking for a specific answer or reference of some kind and likely don't have any interest in joining a new/another "social" environ.

Keep pluggin' away and we'll regrow the community. We're in a spot right now where there's a comparatively small number of regular posters who know each other reasonably well which makes for nice, familiar style conversation, but also runs the risk of seeming cliqueish to the newb. If there's some concern about that it would probably be wise for the established to start creating technical style posts (More like the MP&C threads on fab..........though that's a high bar) to add to the mix. That's what a few of us did when the site was launched and it worked pretty well, though admittedly there was less competition then.