Facebook introduced its location-based check-in service which directly competes with Foursquare and works in harmony with the geolocation service.

The new feature which has been in development for the past 8 months allows Facebook users to check in to any location just as they would with Foursquare but adds a few unique features. The most prominent feature that potentially could put Foursquare back at the drawing board and get privacy activists up in arms is tagging friends during check-ins. The problem with this—like any Facebook privacy fiasco—is the feature being turned on by default for the social network’s 500+ million users. The ACLU has written up their opinion on the new check in service and urges Facebook users to read their take before they participate in it.

The check-in service, which works with the iPhone or any modern touch device sporting GPS, mimics Foursquare’s check-in service. If you’re using an iPhone, updating to the latest version will enable the feature if its available in your region. Fortunately, we were able to test the feature at Digital EYE: we’d say it works more in harmony with Foursquare and Gowalla than competing with them.

Places Beating out Foursquare And Gowalla

The battle of the check-in services is brewing, but it might not be as big as you think. The move seems natural for Facebook considering recent trends and that 20% of Foursquare check-ins are already pushed to Facebook. The two biggest competitors of Facebook’s newly introduced places feature, Gowalla and Foursquare, actually endorse the social networks’ new feature: “Facebook validates the market,” Luedorf of Gowalla said.

Check In From The iPhone App Or Mobile App

The newly updated iPhone App features Places but only if it’s available in your region. However, if your phone supports HTML5 and geolocation services, it will be compatible with Facebook Places. The feature works almost identically to Foursquare, it shows a list of nearby places and tapping a place allows you to check in with a twist; you can tag which of your Facebook friends is there with you. As mentioned earlier, it’s available in our region (unfortunately it’s down for others) and the feature seems cool, but more a component that fits in nicely with Facebook.

Places Has Some Privacy Woes

As with any major Facebook feature, there are some privacy concerns as well. The ACLU has published a post on what to expect from Places and how your privacy controls will be affected.

“Places allows your friends to tag you when they check in somewhere, and Facebook makes it very easy to say “yes” to allowing your friends to check in for you. But when it comes to opting out of that feature, you are only given a “not now” option (aka ask me again later). “No” isn’t one of the easy options.”

Above, is a video published by Lifehacker that details how to turn Facebook’s Places feature off and restrict how friends can tag you using the feature.

Do you plan on using Facebook’s Places? Why or why not? What are your privacy concerns?