You can now download more than 50,000 Audible.com audiobooks on your Kindle via your Wi-Fi connection. You’ve always been able to download Audible audiobooks from the site itself, then transfer them to your Kindle via a USB, but now you can do so wirelessly.
There’s really not much more to this story, other than to mention that when you first sign up with Audible they give you a 30-day free trial.