Hmm, the reply button to submit this comment is just reachable with tab as it should be, so I don't see any issues there?

Have you looked at something like BigBlueButton? I recently used it to give a webinar. They don't have an HTML 5 client yet unfortunately, but they integrate some interesting things to provide video/audio over WebRTC and to their Flash client. I think it uses Freeswitch for the audio/video part.

If you nail the technical issues, you might find that lots of blindies are not that good videographers. You need a high quality stream and preferably a method to let the remote party control the camera zoom. I use "remote eyes" in various situations and had quite some issues focussing my camera in the beginning. I use USB camera glasses or a smartphone, usually just through a Skype connection.