In OpenSocial, the "group" capability effectively represents a shortcut for social graph navigation. This should not be confused with a formal group construct that is in many social business platforms, e.g. Jive calls these "social group".
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@following : The collection of OpenSocial people that the user is following. These are not necessarily following the user.
@followers : The collection of OpenSocial people that are following the user.
The intersection of @following and @followers should be @friends.
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