The document discusses the "Book as a Service" approach to retailing books in the future. Key aspects of this approach include: 1) Hosting books on the cloud to allow for multi-device synchronization, real-time learning and control, and mutable digital artifacts. 2) Enabling social reading features that break down walls between books, readers, and authors. 3) Aggregating content to serve as a hub for readers, publishers, and authors. 4) Providing API access to books hosted on the cloud.