Is this Google's response to MS purchasing skype? Seems like the classic strategy of commoditizing your competitor's business (and they get a 2-for-1 deal since Apple is also wielding FaceTime).
I would guess this is more likely a response to FaceTime. Apple's core business is around getting people to buy iPhones, and FaceTime is exclusive to the iPhone and other Apple products.
http://tools.ietf.org/wg/rtcweb/charters
and this is part of Google's involvement with that.
However the original question is still valid, as this release might have been accelerated quite a bit because MS bought Skype.