With its mobile location-based service, called Google Latitude, Google doesn't keep a log of user locations. "One wonders if this could be applied in some sense to Books," said Jason Schultz, acting director of the Samuelson Law, Technology & Public Policy Clinic.

Google posted a document about Google Books and privacy late last month, but the company plans to release a more formal privacy statement in the coming weeks, according to Google Books engineering director Dan Clancy.

Google often says that privacy is important, but it needs to talk more about what steps it will take, said Chris Hoofnagle, director of the Berkeley Center for Law & Technology's information privacy programs. "The details are what really matter," Hoofnagle said.

"Privacy, by design, requires early intervention," he added.

Last year, Google reached a in a class-action lawsuit brought by authors and publishers who argued that Google Books Library Project violated their copyrights. The U.S. District Court for the Southern District of New York will decide whether to accept this agreement on Oct. 7, but affected parties have until Sept. 4 to submit comments to the court.