I think the comment from mylagoon contradicts the true nature of blogging. If several sites have similar blog content, wouldn’t they each benefit from syndicating each others feeds?
For example, lets say you have a blog about widgets. You have a small following of people that frequent your blog. Another widget blog decides to display your content by using your RSS feed. Now you are getting some of their visitors linking through to your site. It makes sense to reciprocate, so you use the other site’s RSS feed as part of your content. It is a WIN/WIN/WIN situation. You and the other site send traffic to each other. Visitors to either site have their widget information aggregated together in a more accesible manner. Thats also a WIN for them.
I think if your comments were true, blog sites would not provide RSS feeds to their posts. But why would every blog want to live in its own exclusize vacuum? Thats not only contrary to blogging, its contrary to the World Wide Web.