They actually do send an email alert. I didn't find an authoritative blog post on the subject, but here's a post from a reputable SEO site discussing these ema

They actually do send an email alert. I didn't find an authoritative blog post on the subject, but here's a post from a reputable SEO site discussing these email alerts: http://searchengineland.com/google-warning-more-about-bad-link-networks-117079 http://searchengineland.com/google-warning-more-about-bad-li...