New York Times published a talk "A Library to Last Forever" of Sergey Brin, which tries to explain why the Google Books settlement is beneficial to everyone, and would unlock a lot of hidden valuable information available in the Google Books interface: “the vast majority of books ever written are not accessible to anyone except the most tenacious researchers at premier academic libraries. Books written after 1923 quickly disappear into a literary black hole. With rare exceptions, one can buy them only for the small number of years they are in print. After that, they are found only in a vanishing number of libraries and used book stores. As the years pass, contracts get lost and forgotten, authors and publishers disappear, the rights holders become impossible to track down[…][…]in 2004, Google Books (then called Google Print) was born, allowing users to search hundreds of thousands of books. Today, they number over 10 million and counting[…]”. Also check, Sergey Brin’s  "A tale of 10,000,000 books" post on Google blog.