After the Opus codec made it into IETF as RFC 6716, I had a look to see if there is any activity in IETF to standardise a video codec too, and I was happy to discover that there is some activity in this area. A non-"working group" mailing list video-codec was created 2012-08-20. It is intended to discuss the topic and if a formal working group should be formed.
I look forward to see how this plays out. There is already an email from someone in the MPEG group at ISO asking people to participate in the ISO group. Given how ISO failed with OOXML and given that it so far (as far as I can remember) only have produced multimedia formats requiring royalty payments, I suspect joining the ISO group would be a complete waste of time, but I am not involved in any codec work and my opinion will not matter much.
If one of my readers is involved with codec work, I hope she will join this work to standardise a royalty free video codec within IETF.