Why call a restaurant to make reservations when you can simply sign in to their Facebook account instead? OpenTable is an upcoming Facebook integration that will allow users to make such reservations online.

The booking service will cover over 20,000 U.S. dining establishments, and will be available on Facebook's mobile site and newly updated apps for iOS and Android sometime this week.

Mobile users can use Facebook's "Nearby Places" function to locate the nearest restaurants in their area before booking their tables. If the app does well, the stage will be to roll out the feature for other platforms.