Now, you might think that anyone with a blog or website would know how inappropriate and annoying spam comments are, but a few of them sincerely seemed unaware that what they’d done was poor form. So here’s my quick attempt to educate folks on the subject.
Leaving spam comments isn’t just poor form — it’s a poor thing to do for many reasons.
First of all, despite what some poor &/or ignorant marketing folks will tell — and sell — you, spam links are not good for SEO
Via Gracie Passette