I admit it--I am an evangelist when it comes to Audible.com + iPod. I love love LOVE being read to, and it makes so many things better when I can do them while listening to a book.
But! I do have to pay for the books I download. Wouldn't it be better to get books on CD from the library for FREE! and just load them onto iTunes for FREE!?
So, I did a little test--I am currently downloading a book, and I just timed how long a single disc took. Just under 20 minutes. The book I am downloading has 13 discs. That is over FOUR HOURS just to load the dang thing! Audible can do it in about 7 minutes, plus you never have to go in and edit EVERY SINGLE DAMN TRACK to make all the tracks of the same format so they actually play in the right order.
Get a membership, and the Audible books are about $7 each. That works out to, what, $1.75 per hour? WORTH IT!