Facebook has just launched the Shared Activity plugin which allows users to control the visibility of their actions while using apps developed for the platform. The plugin allows Facebook users to set a default audience for in-app activities or adjust the size of the public that previous published actions reach. Former Secretary of State Colin Powell recently spoke about the pros and cons of making more intensive use of social media both in the private and in the public sector. The potential is there, but you have to have leaders who are comfortable with technology and not terrified, Powell said.”]