Over the weekend, Google announced significant changes to its new social networking service, Buzz. Responding to criticism (including EFF's), Google moved away from the system in which Buzz automatically sets you up to follow the people you email and chat with most. Instead, Google has adopted an auto-suggest model, in which you are shown the friend list with an option to de-select people before publishing the list. While a full opt-in model would be less likely to result in inadvertent disclosures of private information, this is a significant step forward.

In addition, Google said it would show current Buzz users the setup process again, giving a second chance to review and confirm the follower list "over the next couple weeks." We recommend that all current Buzz users immediately turn off the public list, and review their friend list before making it public again. (Instructions)

Google will also stop automatically connecting Picasa Web Albums and Google Reader shared items, and allow users to hide Buzz from Gmail or disable it completely.

These problems arose because Google attempted to overcome its market disadvantage in competing with Twitter and Facebook by making a secondary use of your information. Google leveraged information gathered in a popular service (Gmail) with a new service (Buzz), and set a default to sharing your email contacts to maximize uptake of the service. In the process, the privacy of Google users was overlooked and ultimately compromised.

Though Google responded quickly to these privacy concerns, they never should have happened in the first place. While Buzz previously had a lot of these privacy options available, the user interface failed to provide users with the setting users had reasonably expected. Google should follow fair information practices and make secondary uses of information only with clear, unequivocal user consent and control.

Part of the problem may have stemmed from Google's testing process. The BBC reports that Google only tested Buzz internally with its employees, omitting "extensive trials with external testers - used for many other Google services." Google employees are sophisticated power-users who will meticulously review the available settings. However, a good user interface for privacy must work for all users, and match the default settings with the expectations of the users. Only through broad based testing can Google be sure that users are giving informed consent.

Next week Google will face a federal judge and ask for approval of the Google Books settlement. EFF has raised privacy concerns, including the possibility that Google might make secondary uses of the Books information. Buzz's disastrous product launch highlights the danger posed by this possibility, and showcases the need for firm enforceable commitments to protecting user privacy.

Reports are coming in of additional privacy issues.

The Register reports that "Google Buzz is susceptible to exploits that allow an attacker to commandeer accounts and even learn where victims are located." While a security blog now reports this was fixed, Google should conduct a thorough security review to ensure that no other problems persist.

PC World notes that Google's "vanity URL" functionality presents users with an unfortunate choice: Either expose your email address to the general public, or host your profile at a monstrously long numeric URL. Google ought to provide a third, middle-of-the-road option by allowing users to select a simple and memorable URL which is not based on their email address.