At least Microsoft has XMPP federation support in Lync: http://en.wikipedia.org/wiki/Microsoft_Lync_Server#XMPP http://en.wikipedia.org/wiki/Microsoft_Lync_Serv

At least Microsoft has XMPP federation support in Lync: http://en.wikipedia.org/wiki/Microsoft_Lync_Server#XMPP http://en.wikipedia.org/wiki/Microsoft_Lync_Server#XMPP. Otherwise, yes, Skype and Facebook should add federation support. The actual protocol isn't even that important, as long it can be implemented freely.