Now Facebook, Apple, Google and smaller app developers are collecting nuanced details like location data and address-book info, and across a wider breadth of people (more than a billion in the case of Facebook).
To the right, a button lets you open the book (you can also accomplish this by simply clicking on the book, naturally), view more info on the title, delete it from your shelf or find similar books -- yet another spot for some e-book upselling.