But Object RTC is under consideration. I believe (but don't quote me) that most of the efforts at the W3C are focused on this over WebRTC. Also, you'll notice that the IE team is taking a slightly more conservative approach to the new features. Since many features are still in draft mode and can significantly change, they're implementing features as they mature.
MS tried to sabotage mandating free codecs for standard real time communications, but W3C managed to put Opus in WebRTC. Not sure what's going on in parallel efforts in this regard but it's a pretty important issue and MS is on the wrong side in this one.
