indyank - 4:49 pm on May 8, 2012 (gmt 0)
When I was a spotty faced teenager, I was involved with running a message board. I was pretty pleased with the board, and had a sig link pointing to it anywhere I could put one. Emails, online profiles, the works.
It was before Google, and had nothing to do with gaming search engines.
As long as you don't use a keyword as anchor text and was using the site name, it should be clear that it is not for SEO. It is more an exercise done to promote your site or brand and should be fine. The same benefit might not be given if you have a keyword based domain name. Penguin does seem to differentiate this.