Dont take this the wrong way...
Very interesting and informative, seems well designed and direct BUT, you forgot sumtin very important.
A mute button. I know everyone has different music tastes, thats wat makes the world so interestin an all, and theres a lot of people who would hate my taste in music but I couldn't learn anytin wid that "crap" (my opinion only!) playin in the back ground. I realize I cud simply turn off my speakers, but I find it makes tutorials incredibly dull if I dont have anything to listen to (it's almost like bein in school) that I like.
good work despite its lack of a mute button.