Books seem like an old-fashioned way to teach programming. Wouldn't it make sense to create more interactive content so readers/users can try out the code as they go along? I think this is definitely true for beginners learning programming, but shouldn't it also apply to many cases of more advanced programming knowledge?

My plug: My site http://www.learneroo.com has educational modules primarily for beginners learning programming, but I'm thinking of expanding it to more advanced topics. Anyone interested in publishing their content on it?