The RTPSEC BOF today produced some interesting results. The BOF chairs asked the participants whether they would like to base the future protocol work on MIKEYv2, ZRTP or DTLS-SRTP. The group was in favor of using DTLS-SRTP.
Here is the agenda: http://www3.ietf.org/proceedings/07mar/agenda/rtpsec.html
Here are the slides: https://datatracker.ietf.org/public/meeting_materials.cgi?meeting_num=68#wg-rtpsec