The Collaborative Book Authoring sample application enables multiple users to work on the same or different books simultaneously. The idea is that an author logs into a system and he/she sees all the books that are in process, and have been published. Anyone can start a new book and anyone can contribute to a book (so this is quite an open process). Also within a book, anyone can start a new chapter and again anyone can edit the chapter content. The system is built so that only one author can edit a chapter. If someone is editing a chapter content, and another user tries to edit it, he/she will see the most recent save of the chapter content.
When the book is finished, authors will vote for publishing. Authors can vote only once, and a vote cannot be taken back. When all the authors have voted for publishing, the book is moved to a published status, and it is formatted for reading.