So before the speculation and criticism spirals too far out of control, Google decided to nip it in the bud, and address these things right away. A post at the Official Google Blog says:

Because we’re committed to protecting your privacy, we made sure that the searches that we analyze for Google Flu Trends are not drawn from personally-identifiable search histories but rather from an aggregated set of hundreds of billions of searches.

In order to provide a rough geographic breakdown of potential flu outbreaks, we use IP address information from our server logs to make a best guess about where queries originate. To protect your privacy, we anonymize those IP addresses at nine months. And we don’t provide this aggregated, anonymized data to third parties. For more information about the privacy protections for Flu Trends check out our FAQs and privacy policy.

I think what Google is doing with this tool is a genuinely good agenda. The medical field seems to agree. "The earlier the warning, the earlier prevention and control measures can be put in place," said Dr. Lyn Finelli of the influenza division at the Centers for Disease Control and Prevention, to The New York Times. "[T]his could prevent cases of influenza."

Hopefully,Google has put some minds at ease. For more on the tool, and Google.org’s Predict and Prevent initiative (including a video), check out our coverage from yesterday.