Update: All session videos have been removed by Microsoft. No idea why..
Many of the SharePoint Conference 2011 recordings have been posted to YouTube by Microsoft at their sharepointconference channel. I was very happily surprised to see that.
These recordings are complete sessions (many of them over an hour) and not small snippets of 15 minutes or less like many of the other YouTube videos. In the description of the video, it states the session title, code, speaker name, level of presentations, abstract and even which room it too place in at the conference center. Wow!