I'm obviously just too used to the interface! I do have an issue with the fact that adding a book to your "to-read" list is the default, and gets a huge button of its own on every page, but, yes, I guess if you're not used to the concept that the whole thing revolves around putting books on virtual shelves, then it's not necessarily obvious that you click the little "books on a shelf" icon to put it on your "Read" shelf, or the "Currently Reading" shelf, etc.