Although Facebook's Graph Search isn't available to most users yet, once it rolls out more broadly, there won't be any escaping it.
That's because, as Quartz points out, Facebook removed the capability to opt out of searches last month, before it announced the new feature. Sam Lessin, a Facebook product manager, confirmed the change to The New York Times in December, saying that only "a single-digit percentage of users" had opted out when the choice was available. (Of course, with 1 billion users, that still translates to at least 10 million people.)
Search gets personal
Graph Search is an overhaul of Facebook's existing search box. It lets people type in naturally-phrased queries such as "Restaurants my friends like" and "Photos of people from college," and see personalized results.
Graph Search respects the user's existing privacy settings. So, for example, if only your friends can see your photos, no one else will be able to see those photos in their own searches. In other words, Graph Search isn't showing any information that people otherwise wouldn't be able to see.
Still, the addition of a powerful search tool could bring to the surface information that was once buried. As Gizmodo pointed out, someone could use Graph Search to find a list of single female friends of friends, who live in the same city, and who have similar interests. A user might have second thoughts about sharing those types of details now that they're so easy to aggregate. Also, users may not remember all the things they've "Liked" in the past, and some of those things could be pretty unsavory.
The removal of search opt-out isn't too surprising, given Facebook's history of announcing new features that are enabled by default and are tricky to cover up. A privacy settlement with the Federal Trade Commission now requires the company to get express consent for any changes that "override their privacy preferences," but Graph Search may not run afoul of that settlement. After all, Facebook isn't changing what's public and what's private. It's just making information easier to find for people who already have permission to see it.
How to control what shows
Facebook could ease users' worries with more privacy tools related to search, such as the ability to hide your location, photos, or status updates from certain groups of people. That way, users could still keep their profiles somewhat open on a standalone basis without letting those details be aggregated. But I wouldn't count on Facebook making any big changes.
If you're worried about what Graph Search might uncover, you'll need to revisit their privacy settings to see what's visible. To do so, click the gear icon at the top-right corner of the site and click "Privacy Settings." The "Who can see my stuff?" section will dictate what's visible in searches. You'll also want to visit the "Timeline and Tagging" section on the left sidebar, and review who can see photos and posts that you've been tagged in. (When in doubt, limiting it to "Friends" is the best option.)
Keep in mind that users can still hide their Facebook timelines from other search engines, such as Google. To do so, click the gear icon at the top-right corner of the site, click to "Privacy Settings" and look for "Do you want other search engines to link to your timeline?" in the "Who can look me up?" section.