The rumor mill is swirling that Facebook is set to announce the open sourcing of its application platform. While presumably a response to Google-led OpenSocial, the larger question is whether it will matter.
Open source is very good at some things, and not so good at others. For example, if Facebook wants to open source its application platform to make it easier to create and integrate applications into the Facebook platform, open source is good at that. Just look at Mozilla's Firefox or Drupal.