I'm looking into creating a community site for my church. Mostly to have a core place to put data and make it available for different groups of church members (volunteers, ministry areas, etc). One of my requirements is that it hook into other social networking tools (facebook, twitter, etc) for updating our information and for sending notifications. Another requirement is that I want users to be able to log into the site using credentials that they already have. All of our staff have accounts through our Google Apps site, so I would like them to be able to login using those credentials.