Techcrunch is reporting that Facebook has annouced that it's brand new location service goes live tonight, dubbed "Facebook Places." The new service is similar to that of Foursquare, and allows users to check in, as well as geotag photos to a location.
The integration was actually leaked slightly early today, as shown by Techcrunch in the below screenshots, and Facebook says that the rollout begins tonight with the iPhone app, as well as the "Facebook Touch" website. Mark Zuckerberg says the service has three purposes: "[To] help you share where you are. Help you see who's around you. And see what's going on nearby."
The service will allow you to tag people in photos and status updates at the location, and allows you to check in people who might not have an advanced phone with GPS, so that friends are included. Once your friend tags you in, you click "Allow" on the normal Facebook Mobile website and it's as if you checked in yourself. The company also goes on to point out that you can only check your friends in with you when you arrive, and that you can't tag people if you aren't friends with them.
It seems that Facebook is trying to avoid the previous privacy fiasco's they've encountered, and have heavily emphasised the fact that the service will be friends-only from the very beginning, and you will be able to remove any checkin from your profile easily. In addition to this, the user is able to specify who can and can't see the checkins.
Third party applications will be able to utilise the technology, with the read-only API becoming available tomorrow, and the Write and Search API's in closed beta. For more information on the API, visit the developers website.
Update: It looks like Android users will have to wait a while for their update, with the interviewer saying "for Android users touch.facebook.com is good enough."
Update 2: Facebook Places is available to US users only for now.
Update 3: Facebook uploaded a video explaining "Why Checkin?"