After working with several users who were reporting poorly crawled feeds, we've discovered the latest version of MySQL (our database server of choice) has a bug in a certain area of its operation, and this bug tripped in when we did our database upgrade just over a week ago. This caused some feeds not to get updated when they needed to be. We've now 'fixed the glitch', as it were, and lots of feeds are getting added to the crawlers it seems. Things will start returning to normal gradually over the next 24 hours, as that'll probably be the biggest glut of feeds to be processed due to this bug. We apologize for the inconvenience!