Khan Academy is social-network type of learning, where you learn from the community. This is good. But learning from expert educators is also essential and perhaps irreplaceable. There are a lot of short-sighted people, who are marveled by current technologies that allow people interact remotely and immediately jump to the conclusion that we have an answer to learning, while dismissing the entire tradition, culture and knowledge of and about learning that has been established for centuries. Now, if Khan wants to make a quick buck, that's fine. But he's serious about teaching and learning, he should realize that Khan Academy and its approach is only complementary (at extremely great at that) and is not a replacement of the traditional ways of teaching and learning.