No books of any kind have worked in months. I've tried a wide variety of titles and all formats (ebook, mass market, hardcover etc). I know there are some temporary glitches but this is an exceptionally long one. I noticed that no one has posted reviews since Dec so I doubt it's just me that it's happening to... but I posted here, just in case it was just me, so you'd know I really do try to do my reviews here instead of just as text in reading forums.