Compared to Tattler, one of the weaknesses of Managing News is the lack of topic monitoring - where a user inputs a keyword phrase representing a topic and the system takes care of tracking this topic across pre-selected RSS sources.
Soon after we started using Managing News, this requirement came up.
For my work with AdHack, I've started using Managing News as a Drupal-based solution for brand monitoring. As with most Development Seed products, it's a well-designed piece of software that is a joy to work with and enhance.
One of my first tasks was to allow users to mark articles with a star, and to find those starred items in their own channel. In MN, channels are lists of articles that are tagged with a specific set of tags.