As a side note, I love the index on the left hand side of the player, that lets me quickly jump to any section of talk, instead of having to fish for the part when he starts talking about the algorithm, for instance. An awesome feature I wish other websites had too.
Same note, at first I was like "another video I won't watch watch because I'm only curious about one point of the talking" then I saw the menu. Very cool feature, greatly optimize user experience in a simple way
