Facebook calls its service Places and it permits check-ins at a variety of, well, places. It strives to help you understand more about your Facebook friends' preferences and traits of consumption and activity.
It complements, rather than competes with, existing services like Foursquare and Gowalla, and its implications for journalism are not revolutionary as much as they're further impetus to get in the game.
While check-ins are bound to become a commodity in the time ahead --- particularly as services provide it more readily --- the rich stream of data that comes from them will be very useful for all companies in the information business.
Journalism will benefit in understanding more about events and places from the user base willing to give access to their locations. But the stream of behavioural data will be even more important.