Windows Phone users have been yearning for an official Audible app for Windows Phone for quite some time now. Recently, our own Rafael Rivera showed how it's very possible to make an app for Windows Phone using some aspects of the ancient Windows Mobile app of yore. Around the same time, we heard rumblings of a limited beta for an Audible starting to circulate, which gave us hope.
Now, some images of said app have appeared on Reddit by a poster who is reportedly in the closed beta program. He notes that the beta program will be going open in a few weeks and that he won't post the XAP file, so no hope there.
While we can't verify that these images are legit, we have reason to believe that these are indeed real. Hopefully we'll be hearing more in a few weeks.
Update: Confirmed. Paul Thurrott has just posted more screenshots, moving this from rumor to news.