Russell Beattie has an interesting idea - he wants a blog that is completely implemented in RSS. So he’s trying to solve some of the problems like how to allow comments - by putting the commenting form directly in the HTML for the RSS feed (you need to look at the posts in an RSS aggregator to see the web form). One downside to this is that before I make a comment, I usually like to read other peoples comments to make sure that the point hasn’t been raised already. Also the web form typically isn’t going to preload the username / email / weblog fields. I think a better solution would be an RSS / ATOM extension that allows an aggregator to directly post a comment.