A small improvement to Newsblur would be to inform the subscriber if a feed they subscribe to becomes “dead” at some point after it was added. I usually don’t notice when this happens, as my feeds only show “Unread”. When a feed “dies” due to some publisher web error, it will usually have an exclamation point next to it…but that only reveals itself if feeds are set to “All”.
Notification could be done via email…one idea would be to limit such an email to a weekly or monthly report to a Newsblur paid subscriber. The email report on just the “dead” feeds the user subscribed to could include instructions that the Newsblur subscriber should contact the website in question to inform them their RSS feed is no longer working.