Have you seen the collection we're building up on Lanyrd? We have over 3,700 talk videos now, plenty of which are about programming. You can search our video collection here: http://lanyrd.com/video
Do the videos have to be uploaded by a conference organizer, or could I add a bunch of talks from CCC in Berlin? They're Creative Commons licensed, but I'm not associated with the conference myself.
Nice idea, but lacks some additional control, that would allow switching videos in less random fashion. Floating infobox (obviously hideable one) would help here a bit too.
Infobox could have also a real-time generated schedule, i.e. tv guide, queuing some shows and showing estimated time required to watch them (and recalcing it on forced change).
Still, nice idea. I could wish for a way to choose what to watch other than hitting 'next' and hoping, though.