In conversation with industry analysts, Google CEO Eric Schmidt indicated that Google may soon require usernames, passwords and personal information to use their services.
Google Discusses Strategy With Analysts - BizReport:
"- Google is likely to require its users to begin providing personal information to use some of its products and services, said CEO Eric Schmidt. Requiring people to provide their identity and a password to gain service access is common at many Web sites, but would be new for Google. Having more personal information would enable Google to offer more useful improvements, Schmidt said. He didn't provide a timetable or specify which services might require registration."
Thanks to beSpacific: User Registration Down the Road for Google? for the link.