Just for the record: what Google/FB did to #XMPP was not 'embrace, extend, extinguish'. I bring this up because people are focusing on FB developing a divergent protocol/extensions. Maybe that's a valid concern, but it's unrelated to XMPP.
While Google Talk was actively developed, Google folk actively participated in the community. In fact they contributed important extensions such as Jingle, the protocol we still use today for audio/video calls in XMPP, and other bits and pieces.
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