I have noticed a new spammer strategy that has been implemented over the last few months.  Rather than post spammy links in new threads, they simply register on the forum and stay quiet for a few days.  Then, they return to the forum, add their spammy links to their profile page (either in their signature, or in the location where they can put their homepage address).  It's hard to catch these guys since they use this delay tactic.  I checked many of the new members from the past few months and deleted a bunch of people who never posted messages but put hyperlinks in their profiles.  Argh!

The basic train of thought is that search engines rank sites based on the number of links pointing to them.  Even if no one clicks on links, search engine spiders will find these links.  If an important site (like the NY Times) were to have a link to WCF, our rankings in the search engines would probably jump.  Back when I was more into SEO, I recall something about how after the first two or three pages of search results, the number of clicks decreases quite a bit.  Whatever a site can do to keep its site pretty high on the list of search results is for the better (according to conventional wisdom).  Many years ago (around 1999 or so) I joined a free backlinks service, so each site that joined would upload a page on its web site with backlinks to all the other sites which also joined.  This was before I think this kind of thing was really frowned upon.  The thing now is that Google tweaks its secret ranking algorithm from time to time, and so all these spammy backlinks to sites will not necessarily help a site rise to the top.  Still, spammers will do what they think will work...but in the end they're probably simply annoying us rather than helping themselves.