Lauren DeStefanoCheck-in, tag, and venues are just a few key words that you’ll need to know to use Facebook’s new feature, Places. This feature allows users to update where they are and what they are doing through mobile devices such as the iPhone and other smart phones with the geolocation capabilities. Although this may seem like a really interesting idea, the American Civil Liberties Union (ACLU) isn’t so pleased with the new invention.

Facebook Places is a location-based feature that allows users to update their location through a mobile device. You will be able to connect with friends who might be at the same place or interested in joining you at your location. With Places, friends can tag and “check-in” to different locations. The new feature has the same privacy settings as the general profile does and you can also block friends from checking you in and create custom lists with the users that you wish to share your locations with.

“Yes, you can disallow check-ins permanently using your privacy settings, but Facebook doesn’t make that clear to new Places users,” says Nicole Ozer, director of technology and civil liberties policy at the ACLU of Northern California.

Facebook LogoFacebook feels that they have done a good job with their privacy settings and that everyone has the choice on whether or not they want to share this personal information.

“Developers cannot share location information without a user’s express permission, and every user has control over what their friends can share via the API,” says Facebook engineer, Ben Gertzfield.

On a brighter note, Places is thought to raise Facebook’s global ad revenue to $1.6 billion by 2011, says eMarketer research. This is a 165 percent increase from 2009 where they were at $665 million.

The feature will also benefit small businesses and local advertisers because Places will allow them to target users that are nearby or interested in places similar to their own.

Some of the leading competitors that Places is going up against are Foursquare, Gowalla and Yelp which are also location-based social services.

The major differences between these other services are their game features and tip option. Foursquare uses the game technique where you can win virtual badges such as the “Explorer” badge which means that you have checked into 25 venues. The “Brooklyn 4 Life” badge is another popular one that shows that you have visited more than 25 different locations in that New York City borough.

Foursquare also partners with smaller businesses and offers discounts to Foursquare “mayors” which is the title given to the user with the most check-ins for a particular location and you can also leave tips for other users on how that location was.

Gowalla is another competitor to Facebook Places. Different from Foursquare, Gowalla has virtual geocaching elements. You receive a “Pack” that you can hold your virtual icons in. These icons include things such as beer bottles, model trains, instruments, foods, etc. You receive these items after you check into a location and you also get a passport to stamp when you visit different locations.

Many people are saying that Places won’t do as well as these other location-based services. Sure, Places may only have the “check-in” feature, but I feel that Facebook knows what they are doing and have done very well in the past, having over 500 million members I’m sure they have an idea of what will succeed and what wont.