Previously, Google said it would keep such records for up to 24 months.
Google's six-month concession here appeared to placate European regulators, which had indicated they were troubled by the search company's trove of information about individual users.
Franco Frattini, an EU justice, told the Associated Press that Google's new stance was a step forward for privacy in general. "It is indeed a good step," Frattini reportedly said.
But whether 18 months is really that much preferable to 24 months isn't clear. In any event, the 18-month cutoff appears arbitrary. Assuming that Google can somehow improve its product by keeping IP addresses tied to search queries for a period of time, there's still no good reason why that time period should be 18 months.
Certainly, a lot of mischief can occur in a year-and-a-half. Consider, when AOL posted more than 650,000 members' search queries to the Web last year -- the infamous "Data Valdez" incident -- the data released was less than six months' old. Although AOL had attempted to make IP addresses anonymous, the queries themselves revealed people's identities; The New York Times was able to locate and profile one of the affected members within days of the incident going public.