In addition to talk of what the arrival of Facebook Places means for startups like Foursquare, the aftermath of last night’s launch has given rise to a number of questions about privacy.
Notably, the ACLU published a list of grievances almost immediately after Facebook’s announcement, many of them to do with the feature’s option to automatically check friends into locations.
Some of the other concerns raised aren’t necessarily new to realm of location apps, but are amplified by general concerns about such services, the enormous size of the social network’s userbase and the company’s history of privacy-related issues.
Since Places still isn’t enabled for many people (Facebook is working on it), including those outside of the U.S., Mashable reporter Christina Warren and I decided to test out the features — especially the controversial tagging option — on the web and on our mobile devices this morning. The results are illustrated in the gallery below:
Facebook Places: Privacy Features Walkthrough

After tagging Christina in my checkin, she receives a notification on Facebook similar to the type of notification you'd receive for a comment or "like".
Facebook Places: Privacy Features Walkthrough

Since this is the first time Christina had been tagged, the iPhone app asks her if she'll allow me to check her in. The other option is "not now," which, if selected, means she'll continue to get this notification in the future when other friends tag her.
Facebook Places: Privacy Features Walkthrough

Christina is able to see that I'm checked in to Jamba Juice, as well as the whereabouts of her other friends.
Facebook Places: Privacy Features Walkthrough

I am able to check in both myself and Christina at Jamba Juice (since she allowed my tag). In reality, Christina is hundreds of miles away in Atlanta (I'm in New York). While a rather harmless example here, you can imagine the ability to tag friends in checkins being used in more devious ways.
Facebook Places: Privacy Features Walkthrough

The "Here Now" feature shows that I'm at Jamba Juice. Since the rollout of Places is limited at the moment, it's not surprising that I'm the only one checked in here. However, if there were other people checked in, this feature would list them, even if I'm not their Facebook friend (this is similar to Foursquare).
Facebook Places: Privacy Features Walkthrough

Back on the Facebook website, under "Privacy Settings" I can see that places I've checked in is currently visible to friends only. Clicking "customize settings" brings up a slew of additional options.
Facebook Places: Privacy Features Walkthrough

Now on the "Cutomize Settings" page, under "Things Others Share," you can enable/disable the ability for others to check you in. Note that this feature is enabled after you've allowed someone to check you in the first time, per my earlier checkin of Christina.
Facebook Places: Privacy Features Walkthrough

Still on the Customize Settings Page, I can enable/disable the ability for others to see me on the People Here Now feature, per the earlier example at Jamba Juice.
Facebook Places: Privacy Features Walkthrough

Again on the Customize Settings page, after clicking "Customize" from the pull-down menu next to "Places I check in," I have granular control over who can see my checkins. I can make it visible to friends, friends-of-friends, only select people or the network I belong to. I can also block individual people -- in this case, my boss Pete Cashmore (nothing personal, Pete).
Facebook Places: Privacy Features Walkthrough

Another setting to be aware of is under the "Applications, Games and Websites" area of Facebook Privacy Settings. A new "Places I've Visited" option, when checked, enables friends to access your location information when using third-party apps (h/t reader Patrick Barbanes).
Reviews: Facebook, Mashable
More About: facebook, Facebook Places, geolocation, privacy
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