<http://schema.org/description>
"As Group Messaging is all the rage these days, it'll be interesting to see how the world's biggest social network, Facebook, is going to implement it. The new Facebook Messages-service ..."^^<http://www.w3.org/2001/XMLSchema#string>
<http://thenextweb.com/facebook/2011/04/03/how-group-chat-could-dramatically-improve-facebook-apps/>