What does james gleick mean when he talks about "the gloom that has fallen over the book-publishing industry"?

In his 2008 article for the New York Times, James Gleick talks about "the gloom that has fallen over the book-publishing industry" to describe the the negative impact of digitalizing books in the book-publishing industry.

In this article he describes the already decline in paper-books sales due to the rise of digital platforms such as Kindle, epub, etc, and how the future of book-publishers looked grimer because of an agreement between authors, publishers and Google to allow the scanning and digitalizing of books to make them accesible in website and digital platforms.

This agreement would be dramatic for the sectors of the book-publishing industry dealing with marketing, archiving and distributing physical paper books.