I’ve heard it said that forum signatures are weak and worthless links to pursue by other SEO’s.
While this might have some grain of truth in pagerank terms, it couldn’t be further from the truth in simple referral traffic.
If you participate in a busy forum, closely related to the subject of your website then a signature link is almost guaranteed to drive traffic to your website. I run a holidays in Scotland website. I’m also a member of a travel forum. I watch out for any new threads related to Scotland and post on them. Chances are the people interested in those threads will be interested in my site and follow my signature link.
Using a humorous sig link can also help drive traffic from even an unrelated site. My friends run a Food and Drink website. One of their buddies stuck “F*** Jamie Oliver, this is ‘Propah’ food” in his signature on football and other forums he uses and drove loads of traffic to the site before it had even been picked up by search engines.
So don’t give up on forum sig’s. They still carry plenty power.
