It’s getting more and more difficult for nefarious site owners and black hat SEO’s to game the search engines for SEO and traffic so they’re looking to your site for any back links they can get with a comment. Beware!
a look at the value, some hype & some confusion in website comments
Looking at blog pingbacks, blog comment spam and the potentially negative effects
Be sure to review comments carefully before approving
With vindictive people, bot spam and a potential for less search engine trust, comment moderation is a business requirement.