Google Buzz has been rolled out to 150M Gmail users around the world. In their own words, it’s a service to start conversations and share things with friends. Cynics have said it’s a megalomaniacal attempt to leverage the existing user base to compete with Facebook/Twitter as a social hub. Privacy advocates have rallied sharply around a particular flaw: the path of least-resistance to signing up for Buzz includes automatically following people based on Buzz’s recommendations from email and chat frequency, and this “follower” list is completely public unless you find the well-hidden privacy setting. As a business decision, this makes sense, the only chance for Buzz to make it is if users can get started very quickly. But this is a privacy misstep that a mandatory internal review would have certainly objected to. Email is still a private, personal medium. People email their mistresses, workers email about job opportunities, reporters email anonymous sources all with the same emails they use for everything else. Besides the few embarrassing incidents this will surely cause, it’s fundamentally playing with people’s perceptions of public and private online spaces and actively changing social norms, as my colleague Arvind Narayanan spelled out nicely.

Perhaps more interesting than the pundit’s responses though is the ability to view thousands of user’s reactions to Buzz as they happen. Google’s design philosophy of “give minimal instructions and just let users type things into text boxes and see what happens” preserved a virtual Pompeii of confused users trying to figure out what the new thing was and accidentally broadcasting their thoughts to the entire Internet. If you search Buzz for words like “stupid,” “sucks,” and “hate” the majority of the conversation so far is about Buzz itself. Thoughts are all over the board: confusion, stress, excitement, malaise, anger, pleading. Thousands of users are badly confused by Google’s “follow” and “profile” metaphors. Others are wondering how this service compares to the competition. Many just want the whole thing to go away (leading a few how-to guides) or are blasting Google or blasting others for complaining.

It’s a major data mining and natural language processing challenge to analyze the entire body of reactions to the new service, but the general reaction is widespread disorientation and confusion. In the emerging field of security psychology, the first 48 hours of Buzz posts could provide be a wealth of data about about how people react when their privacy expectations are suddenly shifted by the machinations of Silicon Valley.