Find out about the new feature on Facebook

(NBC) - Facebook's made it easy for its 500 million customers to connect virtually. Now the social networking site is helping with face to face connections.

"There are a lot of very harmless reasons why you'd want to use this," said Tech Editor Wilson Rothman.

Facebook's new 'Places' feature automatically puts the word out when a user checks in via cell phone from a given location. All of their Facebook friends will know.

"Nine out of 10 times, it's not going to be an issue if people see you're at a pizzeria for an hour and a half," said Rothman.

It's territory pioneered earlier by such websites as Foursquare and Gowalla, but with Facebook, there is a hitch.

"If you want your friends to see where you are in a particular place, you have to also let strangers see where you are," explained Rothman.

That's because if your locale has a Facebook page, your presence will be noted there too for any Facebook client to see.

Facebook friends can also check you in unless you adjust your privacy settings to prevent it.

"I think they're going along the same pattern that unfortunately, gotten them an enormous audience, even if privacy activists are very concerned," said Wilson.

Facebook users can choose to skip the "places" feature all together. The company has made it an opt-in offering.

But for some, that's easier said than done. It means navigating the site's multiple privacy settings.

"I think there should be some nuance there that there definitely isn't at the moment," said Rothman.

But for Facebook, "Places" represents a potential new revenue generator for advertising and for clients. It's the latest twist on socializing.

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