Scribd puts me in mind of the circulating library. Early in the 20th century, many people consumed fiction from a circulating library - simply another name for a private library. Users were charged a fee for the privilege of borrowing books from the library. Instead of buying one book, the customer paid an annual subscription and could borrow books for a set time. Typically, the subscription enabled the user to borrow just one book at a time. For a higher subscription, the customer could borrow more books at once.
(There is an excellent website with details about circulating libraries here).
Now fast forward to digital books. Scribd is one of several recent examples of digital subscription platforms - others include Oyster Books, Bookboard, and 24symbols. For an annual subscription, (in fact $8.99 per month), Scribd users have access to hundreds of thousands of titles, which they can temporarily download to their local device (up to 20 titles at any time). All of this is very similar to a circulating library. Plus, Scribd offers book reviews by other customers, and recommendations (if you liked this, you'll like that!). This week Scribd bought Librify, a provider of additional functionality for subscription sites. Described by Publishers Weekly as "the Book of the Month Club for E-books", Librify added just a little extra functionality that Scribd clearly finds vital. Essentially, Librify provides the book club capability - a group of users can buy one discounted ebook each month. They can then schedule meetings of their book club and share comments with other users as they read.
All this might seem a long way from the book as a simple object. Whether digital or print, books are read in a similar way. They have a start and a finish. Once you have finished them there's not usually very much you can do with the physical book. The circulating library offers a very rich model of how books are used. Once you start to get involved with individual user journeys with books, the path becomes considerably more elaborate. Just imagine replicating the circulating library in an academic context - no need, given the existence of the vast academic libraries. But what about adding the ability to comment on and to read books in groups? Which academic library has thought of providing that functionality?