Google Apps linked with Google Groups

Google has linked its Google Apps suite with the Groups service, making it possible to share documents, sites, and calendars among defined groups of people. For example, a spreadsheet shared with a Google Group will be accessible immediately to anyone joining that group, or rendered inaccessible to those leaving the group. Across Google's various applications, including Docs, Sites, Video for Business, and Calendar, groups can be given access by having an invitation sent to the group's e-mail address, rather than to an individual's e-mail address. Until now to share these items, you had either to make them entirely public, or share them on a person-by-person basis.