Platform wasn't sold that way initially, in fact they bragged about how something as core as Photos or Gifts could be replaced by a superior version created by

Platform wasn't sold that way initially, in fact they bragged about how something as core as Photos or Gifts could be replaced by a superior version created by 3rd party developers. I found the difference now - it's in the description of the main prototypes page: "Prototypes are product experiments built by Facebook engineers". http://www.facebook.com/apps/directory.php?app_type=6 http://www.facebook.com/apps/directory.php?app_type=6