Most of it is done automatically, and they don't discriminate in forums. True, in this forum, most people are highly unlikely to click on any of it, but in other forums it's a different story. Fact is, if people didn't click (and buy) there would be no spam.
I'm pretty proactive about getting rid of the spammers before they post anything. I look at user accounts multiple times a day to look for telltale signs and ban and delete accounts if they even look like they may spam the boards. Obviously some sneak by. I have some very minor modifications planned to the registration process (if I ever get the time) that I hope may gum up the works for the spambots. For now, keeping a close eye works well enough.
Not to mention that users of the TD forums report it very quickly, which helps me to get rid of it quickly.
