• by Wendy Davis  @wendyndavis, January 24, 2012

Google said Tuesday that it will revise its privacy policy to allow it to mesh together information about signed-in users across a variety of products, including Gmail, Android, and YouTube.

“Our new privacy policy makes clear that, if you’re signed in, we may combine information you've provided from one service with information from other services,” Google's Alma Whitten, director of privacy, product and engineering said in a blog post. “In short, we’ll treat you as a single user across all our products, which will mean a simpler, more intuitive Google experience.”

Google apparently intends to use the combined data to create detailed profiles, which it will use to personalize its services and also for ad-targeting.

Whitten justifies the move as follows: “We can make search better -- figuring out what you really mean when you type in Apple, Jaguar or Pink. We can provide more relevant ads too. For example, it’s January, but maybe you’re not a gym person, so fitness ads aren’t that useful to you. We can provide reminders that you’re going to be late for a meeting based on your location, your calendar and an understanding of what the traffic is like that day.”

The changes go into effect on March 1. Google is telling users that they can't opt out of the new policy, though users can continue to opt out of receiving ads targeted based on their Web-surfing history.

Google's announcement drew a sharp reaction from Rep. Ed Markey (D-Mass.), co-chair of a House bi-partisan privacy caucus. “Google’s plan to change its privacy policy raises important questions about how much control Google users will have over their personal information,” Markey said in a statement. “While it is undetermined at this point how the policy will impact specific Google services, it is imperative that users will be able to decide whether they want their information shared across the spectrum of Google’s offerings.”