how exactly WebRTC going to solve raised questions regarding privacy ? in light of a fact that, for ICE to operate, you need STUN server and exchange ICE candidates (and SRTP keys) through WebRTC server
after source code reading (and chrome dev console output observing) you have to realize:
1. there is need of 'signaling server'
2. session encryption keys are exchanged through that server
yes, anyone could setup their small server and call through it an make sure tls / ssl cert of their server is intact etc. that will not be a case for avg Joe. not to mention tat browser itself will be an attack vector.
first, make yourself familiar with WebRTC. it will require server side signaling. demo by google: http://www.webrtc.org/running-the-demos#TOC-Demos
sending srtp session keys over that signaling server sounds interesting