I’ve dabbled at learning a little at the KhanAcademy.org site.Salman Khan proposes that his online lessons aren’t a replacement for the teacher, but rather for the textbook. In and of itself, this would seem to offer large possibilities for independence in education - any large institution could create its own video lessons, and evade the constraint of the limitations of available textbooks.
But clearly, a good online course would not require a teacher if a mentor is available to the student. And who is to say that mentoring can’t be online? Khan says he has the ability to track the spots in his videos which tend to hang up some students, and thus can make videos which do not tend to cause hangups.
IMHO, the need exists for a utility which would be the analog of hypertext, but for video. A student hangs up at a certain point in a video, and flags that problem for his mentor. The mentor then has the ability to put a “hypertext” link in the video, and any subsequent viewer of the video can click on the link and either read the mentor's text, or see the video which the mentor has made. Obviously that could get out of hand if too many mentors chimed in, so somebody would have to control the clutter.
That could help, but I also know from learning through online communication that having an online mentor does not and cannot replace a classroom instructor who does his or her job properly. One could try having someone explain a concept they are struggling with entirely through email vs face to face interaction and see the difference. Even communicating through something like Skype does not entirely compensate for the drawbacks. I have tried substituting classroom type mentoring with online mentoring entirely and it does not work. Kahn does say that he can track the spots in his videos that cause hangups, but he also says that cannot replace personalized, face to face teaching with someone who is learning the whole subject from square one. He does not have anything close to a method which would allow him to properly address every struggle that those who watch his videos have.
And at the moment, a good online course still requires a teacher to set up the course and write lectures and explain difficult subjects. Some mentoring can be done online but it definitely cannot be done, at least not at the moment, using an automated, non-human system. Even online mentoring would still clearly require a sort of human interaction that cannot be replaced with a sort of robot.