In April 2010, Facebook announced the Social Graph API. The Social Graph API uses REST, JSON, and OAuth for authentication. It relies on standards much more than the original Facebook platform. The trend toward standardization has continued at Facebook. With the announcement of iFrames support for Pages, Facebook has pulled the plug on their proprietary FBML format. No new FBML applications may be created after Friday.
Past platform changes on Facebook and communication about those changes had been a source of frustration for some developers. Facebook has been addressing developer outreach and support through their Operation Developer Love program. There are weekly blog posts, bug report, and fair warning on announcements.