While searching for some more information I came across something on the Hachette Book Group Catalog pageThere is a link to the catalog for the Little Brown and Company, it is rather a large PDF file (81.8 mb) but included in it are two snippets of interest.
The first is shown to the left, it is a general letter about future publishing, and includes this paragraph about S. -
"Our Fall 2013 list may well send you off the cliff. J.J. Abrams - one of our world's most creative, brilliant, and canny storytellers - leads the list with a collaborative novel with PEN Hemingway-nominate novellist Doug Dorst. It's a book that is so surprising we cannot reveal its contents. It's a story for J.J.'s millions of fans, a story for people who love books. I can promise that there is nothing in this book that will not surprise you."
The second letter is contained on the catalog page for the novel, I'll let you read it yourself, but it gives an insight into where the novel originated for J.J.The only other real information on the page is that the book will be 352 pages long.
