On the same side of the intenet coin as SEO/SEM is traffic analysis. You really can't, or shouldn't, have one without the other. While SEO/SEM activities do their best to drive traffic to your website without the activity of traffic analysis you would never know if anyone has visited your site - along with a bunch of other very important peices of information.

As part of a set of services I provide I can monitor your website and send a weekly report to you detailing several important metrics involving your visitors.