For the first time, Chrome and Firefox can "talk" to each other via WebRTC, a new set of technologies that brings voice, high-definition (HD) video and communication to the web browser.
From the very beginning, this joint WebRTC effort was embraced by the open web community, including engineers from the Chrome and Firefox teams. The common goal was to help developers offer secure communications, integrated directly into their web applications.
Thanks to the work and participation of the W3C and IETF communities in developing the platform, Chrome and Firefox can now communicate by using standard technologies such as the Opus and VP8 codecs for audio and video, DTLS-SRTP for encryption, and ICE for networking.
To try this yourself, you'll need desktop Chrome 25 Beta and Firefox Nightly for Desktop. In Firefox, you'll need to go to about:config and set the media.peerconnection.enabled pref to "true". Then head over to the WebRTC demo site and start calling.