I much prefer reading as my method of getting information. An important thing to remember is that most audio/video is aimed at a general audience. That means a lot of it is too dumbed down so that people who don’t have a basic understanding of a topic can grasp the information. Plus, it’s a lot easier to reread a sentence then recuing a CD or DVD and thus books can get away with more complex explainations. Remembering my days as a chemistry major in the 90’s, I can barely remember any information that wasn’t presented in written form.
Reading.
Bullet point format.
No extraneous information.