Yesterday we found a huge problem with our rss feeds. It became apparent to me when we made a change to our feed and suddenly there were 11 duplicate entries in bloglines for all of our reported items. I am so sorry!! Quickly it occurred to me how annoying something like this would be to other readers. It is very frustrating when a new post appears in bloglines that you have already read and there is no indication as to what has changed. This happens frequently with the WOMMA News and The Womnibus feed for some reason. I can't tell you how many times I have gone into bloglines to see that they have added a new advisor, Dr. Andrea Wojnicki. I'll admit, every time this happens I debate on whether or not to delete the feed in question.
I haven't done any research on this, but there should be some standard to notify users that a change has occurred to a post. What I have noticed many people practicing is just indicating at the bottom of the post that a 'Correction' has been made. Unfortunately when one decides to change the title this will still create a duplicate post because most software uses the articles permalink to indicate its uniqueness and when a title is changed the permalink changes because that is used to create the path. This is something that should probably be changed so aggregators don't have this issue in question.
So, for now, I am happy to report that "we, uh, we fixed the glitch". This is just another example of how powerful products using SaaS can be in web applications. One little change to some code and all of our clients are able to take advantage of this correction.