"While TrackBack is a useful tool, it isn’t used as much as many people would like. For TrackBack to be used, it must be supported by the blog that you’re “TrackingBack” to. It is also necessary that your blogging tool support TrackBack or that the other blog offers some form of “manual” TrackBack. […] There are many applications of subscriptions to “Referenced URI’s” and I’ll try to write about some of them in future postings. One that I’d like to mention now is the application of tracking discussions on a common topic across otherwise disconnected blogs. To track discussion of a topic using PubSub.com, all you need to do is create a URI that will be used as a flag to indicate that someone’s blog entry addresses a topic."