This summer, I've learned about some software/services -- they're made by various companies, so I won't single any of them out here -- that combine screen capture and audio recording abilities. They'd be useful for instructors: if I had a student's paper in electronic form, then I could put it on the screen, record myself making comments about various parts of the paper (while using the cursor to highlight those parts), and save all of that into a file that that student could access. The lower-tech version is simply to record comments and send those to the student -- I know some instructors who used to do this with cassette recorders.
What are some of the possible benefits and/or pitfalls with this method of giving students feedback? What are your experiences, and your students' experiences? Does it, as some have claimed, make grading faster than the "write or type your comments onto the paper" method? Does it lead to students who take more of your feedback more seriously?