You can find discussion of various aspects of ORTC's design on the public mailing list archive for the ORTC community group here: http://lists.w3.org/Archives/Public/public-ortc/. In addition to using JavaScript rather than a legacy format to configure the real-time protocols, ORTC addresses some useful real-world scenarios such as mixing and matching data connections.
- doesn’t truly solve goal of interoperability with legacy systems (eg. SIP)"
from
"the Chief Architect at Hookflash and author of the new P2P protocol, Open Peer. I used to be the CTO/ Chief Scientist at Xten, now CounterPath, and I’m the original author of the X-Lite/X-PRO/eyeBeam SIP softphone clients. "
As someone that has spent the last 18months building on WebRTC I can agree with all of Microsofts points - particularly offer/answer state machine which is hugely problematic.