Bob, Thanks for the question. The analytical side of RSS is still emerging and as you stated without having users register when subscribing to the feed it will be difficult to fully understand who they are from a CRM perspective. In terms of understanding the "visitor", the current stats available for subscribers (when visiting your site from a feed) are very similar to what is available for websites based on the log files produced by a visitor session. A new element to RSS that is going to be key to understanding the reach is Impressions. This would be a count of the number of times the feed is actually being displayed in a reader (a similar concept to pay for performance advertising impressions). Extending this concept to understand the number of users resulting in these impressions would complete the picture. One would then know: Number of Subscribers; Number of Impressions per Subscriber; Click Throughs. At this point the various classical e-commerce conversion metrics could be applied, completing the cycle. Analytical tools are emerging for RSS - one service www.feedburner.com has some interesting ideas. If one publishes the feed through their service, a lot of custom analytics are available.