Fair point. But I looked on Reddit and couldn't find the kind of thing I'm talking about (r/bookclub chooses one book a month by vote, and r/ReadingGroup seems

Fair point. But I looked on Reddit and couldn't find the kind of thing I'm talking about (r/bookclub chooses one book a month by vote, and r/ReadingGroup seems like an overwhelming sea of random posts). I think also the fact that it contains clubs for many different media is a bit of a handicap, since the book content gets swamped, and there's a searchability problem. (Reddit's UI isn't great at the best of times, anyway.) GR has a built-in audience of a wide range of readers, so they're better positioned to do this kind of thing.