This is a little late, but hopefully adds something to the conversation. I see lectures as an information retrieval and encoding problem and recorded audio can be a useful resource if used properly. I record lectures, and rarely listen to them but if for some reason my notes are vague (feeling sleepy, space out), it's nice to have the recording to help clarify things. I use Notebook which timestamps all of my notes and allows me to navigate to exactly the time in the recording when the words were typed. It's pretty handy. I think some other apps do that. I know that the Livescribe pen does.
Also, if I get confused in lecture I can simply write "confused". Then I can go back to that section and listen over and over to help my understanding. I'm not as quick as some people in class, so hearing something once is sometimes not enough. That being said, I definitely want to bump up my note taking skills too.