"Google has responded to European regulators who have suggested that Internet Protocol addresses of users be considered personally identifiable information. Not surprisingly, it disagrees.
The issue matters because the standards for what companies do with data that can be traced back to an individual are subject to tighter rules than other information they use — as they should be. Google records the I.P. address associated with every search it handles." – Content courtesy of Google Says I.P. Addresses Aren’t Personal – Bits – Technology – New York Times Blog