How big (or small) is the flight simming community worldwide?

Yeah, it's true that I know nothing about your numbers. But I did once run a torrent tracker for freeware addons, and I'm currently running a freeshell, and unfortunately, the vast majority of the signups are from spambots. I'd say the ratio of spambots to legit signups on my site is about 10:1. We are running a very small site, so I imagine the ratio will be far higher at our site compared to avsim. While there are tools to keep spambots away, they will still generate hits, even if they are prevented from posting, or even signing up.