Facebook has opened up its application directory so that search engines can index third-party services created for the site and what users say about them.

The move should provide developers of Facebook apps with more visibilty and a wider audience.

On its blog, the social network says the move will allow everyone to discover applications, not just users of the site. It adds:

“In addition to containing information about your applications, a large part of why app about pages are useful is because of what users have to say about your app. So, we’ve decided to allow logged out users to read reviews and the discussion board so that they can get a full picture of what an app has to offer.”

This follows the social network’s decision back in September to allow public access to Facebook user profiles.

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