Google has just added WebRTC to the Chrome source tree. WebRTC (real-time communication) consists of Jingle, VP8, some voice codecs and other audio software they bought, and various NAT traversal algorithms. The IETF is standardising it and Mozilla and Opera are committed to shipping it. Somewhat interestingly, a bunch of Skype engineers seem to have been involved in it too.

http://sites.google.com/site/webrtc/blog/firststeptowardchro...

http://tools.ietf.org/wg/rtcweb/charters

I don't know how usable it is right now, though Google is apparently rewriting their Google Talk stuff to use it. But it seems like the future.