Google have so many different services you can communicate through, Google Talk, Google+, Google Voice, and oh-so-many more - how could the Mountain View-based search giant bundle all of these together? With their rumored 'Babble' service, that's how.
Babble is reportedly how Google will unify their communication services, which would be powered by the XMPP protocol. This means it'll be future-proof, scalable and versatile enough to morph its way around the many services Google currently use. This information is coming from "multiple sources" of Geek.com, and the XMPP-based nature of Babble will see Google forcing you to use their new service, their way - which will push some people out of the Google bubble. Those who continue to soldier on will most likely enjoy a super stable, well-featured service.
There's no ETA on Babble, but I would guess that we'll hear more about it at Google I/O in a few months time.