The Web Hypertext Application Technology Working Group (WHATWG) is working on a specification for the future of HTML in Realtime Collaboration:
On the first sight it covers a lot of the topic developers are waiting for a long time:
It seems like the nature of the communication is based on a Peer-2-Peer communication, which obviously must sound like christmas in some ears :).
First: The WHATWG is not reallye "the" specification group of HTML, the real specs will be done by the W3C. There are also specs in process at the w3c http://www.w3.org/2011/04/webrtc-charter.html.
If looking more closely at the specs you have to admit that there are some open questions on both sides, the w3c and even more at the WHATWG.
Some very basic question is if the Codec that will be used for encoding the audio and video will be an open one or not. I do understand that manufactors have little interest in publishing a codec that is suitable for everybody. On the other hand it could be quite difficult if different browsers support different codecs. Or even worse if big companies like Google, Microsoft and Apple agree on certain Codec, license each other but lock-out browser vendors that don't have 20.000 patents to claim each other.
Having an open standard for realtime communication does not necessarily mean that everybody can implement those specs. If there is no open codec available that all browser platforms do support that could even lock-out small software vendors.
A very basic technical question is also how they plan to fix the Firewall problem: Peer2Peer is nice, but even Skype has a fallback method to proxy data through a central server.
But looking at the milestones planned in the specification (End in 02/2013), there might be also major changes in those specs.