they have added an awesome selection of Adobe epub books. I didn't even know they offered epubs! I just checked out Gate at the Stairs by Lorrie Moore, which I've been wanting to read since it was published. They also have the first two Millenium Trilogy books, a ton of John Grisham, The Help and a lot of other bestseller-type books. Go check it out!
http://ohdbks.lib.overdrive.com