The web's worst kept secret of recent months finally became a reality yesterday when Facebookunveiled its widely anticipated Facebook Places location tool.
Apart from inevitably having a massive impact on existing geo services such as Gowalla and Foursquare, Facebook Places opens up a fantastic array of possibilities for the travel brands and travellers alike.
The reason why Facebook Places will make travel companies sit and up listen to ideas around geo services and location check-in is easy: 500 million members having the ability to pinpoint where they are and share information with friends is suddenly very important, and more than just a quirky tool that tech media luvvies FourSquare and Gowalla have produced.
In other words: volume and audience penetration will trigger a change in thinking.
So how does Facebook Places work?
Well, pretty much the same as its counterparts. A check-in tool allows users to see where they are on a map (via a mobile device's GP - for now, only on the iPhone) and simply mark their position and activity on their profile wall.
Over time the system - similar, once again, to Foursquare and Gowalla - will begin to build a database so the user can select from a pre-populated list depending on the location.
Facebook hasn't included the gaming element pioneered by Foursquare, so there are no mayorships or badges to be won. It's a simple location engine, nothing more.
So why the fuss? There are two interesting elements in play here, covering how companies and travellers might use Facebook Places.
The simpler of the two is about individual members of Facebook. While it may have taken time for Facebook to evolve to its current state, adding location check-in seems pretty much the most natural thing the social network could do.
Hundreds of thousands of active members are posting status updates, pictures, video and links about their activities - adding a tool so people can pinpoint where such things took place is obvious.
Travellers will be notifying their friends of their location, commenting on or posting media relating to destinations, hotels, aircraft and other travel services. They will be making arrangements to meet friends at a destination, collectively posting confirmation of their arrival, etc.
For the everyday traveller the tool will simply make Facebook a better, more fun, more interactive social network.
2. Travel companies
For brands, Facebook Places is an opportunity and a challenge.
A hotel, airport, airline, activity, destination service will surely be encouraging users to check-in on Facebook, thus sharing a branded location around an individual's network.
Clever brands will soon fathom out a way of incorporating check-ins into a module on their fan pages, or illustrate which fans have visited a location or product it runs.
The amount of potential data available through monitoring check-ins will be extraordinary, giving companies a unique picture of what types of people are visiting a location, what they do once they are there, who they hang out with, what are their other interests.
A process of dealing with both positive and negative feedback via check-ins will be something that needs to be tackled quickly.
Almost every travel product will have some kind of "I HATE this hotel - it's dirty and the staff are rude"-type check-in soon enough, but how they address such messages, especially as there are (inevitably for Facebook) complicated opt-in and opt-out options for displaying check-in data.
Marrying Facebook Places, Facebook Questions and its existing features and suddenly the social network that people play around with a lot (too much!) takes on a major new place at the centre of the web - and should only be ignored at a company's peril.