Exactly. Add the word "related" to blog post or forum thread. The link must look natural. Google has made it clear that excessive links from unrelated sites are a potential target. That would mean signature links. I suspect that they do not affect a site until they reach a certain threshold percentage of the total links to a site.
Originally Posted by iowadawg
"Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." -- Benjamin Franklin