Google has made dealing with the more calculated end of the backlinking game a priority over the last 18 months, and there's an edge of panic coming from certain quarters - namely, SEO agencies. Matt Cutts, who heads Google's spam team, hints in an interview that the company may soon be going after spammy links in infographics. Original Story
Any commercial link will be deleted and reported to Mollom as SPAM. As such, we highly recommend against including commercial links in comments. Even comments with a reasonable amount of relevancy to the subject will be deleted and reported as SPAM.