I don't want to thread creep here but we've been seeing a lot of board spam and I think I'm going to have to add Gizmo's plugin. I want to add a couple of observations.
I could be wrong but links in the profile pages are NOT no_follow. SD you might want to change this in the next version.
So, with the above in mind, I think most spam these days is SEO spam, black hat link building. I did an audit on all of our links in 'homepage' and 'autosig' to, ironically, do a link building campaign. What I noticed is that a lot of spammers will register, add a link in their profile, and call it good. Now, in reality, that link isn't worth a ton of "link juice", but on a site with a high Domain Authority it's better then some other sources.
I'd encourage anyone who cares about their board to do an audit of their links to see what is pointing out.
