LibraryThing has an interesting page with user stats. It includes some fairly mundane things like the largest libraries and newest additions. The interesting thing to me were rankings of books and authors by ratings and tags. I thought it particularly interesting that Chesterton's The Everlasting Man came out as the number one book according to user's ratings. Neat, huh? (I really need to read it myself still!)
Speaking of which... Dr. Thursday has some great quotes from The Everlasting Man for Holy Week.