BookDiscussions.com is my attempt to provide a solution.
This site is very much a "work in progress," so your feedback and help are most encouraged! By virtue of other pressing projects, BookDiscussions won't get a lot of attention from me right now, but I didn't want to delay in making it available to others who might benefit from it. In the same breath, let me say that if there is someone for whom this is a real passion and you want to help somehow, let me know so I can bring you into the mix here!
Because I'm pretty dedicated to the education space, BookDiscussions will be first and foremost a student/family-friendly site, so please keep the language clean. I've started a group right off the bat for Sir Ken Robinson's The Element for those planning on attending or listening my interview with him tomorrow night.
To set up a book discussion, click on "Book Groups" at the top of the site and then "Add a Group." You'll have some choices about your group--a good starting place is to choose the "Discussion Form" and "Text Box" features to start with, and then decide if you want anyone to be able to join or only those you accept (safest). I do not recommend that you allow the option for members to send messages to the entire group.
Because book discussions groups are often for a particular audience, there can (and should) be more than one group for any book. I'm going to start seeding the network around the book authors I interview at my FutureofEducation.com and Conversations.net series. These are live events held in Elluminate. If you want to hold your own free, live, public events to do the same, more information is at the Host Your Own Webinar Group in LearnCentral.org or contact me directly.