totalodds - 5:09 pm on Jun 25, 2013 (gmt 0)
@ColourOfSpring you're exactly correct. People are now simply blasting automated (do-follow) blog comments for the "commercial keyword" you are ranking for.
Unless your website has high authority (eBay, Facebook, Twitter) you can fall victim.
I think Google need to completely devalue all blog comments from their algorithm and treat them a no-follow.