MyFacebook Connect is the ultimate solution for MyBB <-> Facebook bridging, featuring smooth login and registration.
Version 2.0.2
Dependencies PluginLibrary, PHP cURL, Server-to-server connections support
Author Shade
MyFacebook Connect lets you and your users register and login with Facebook on your MyBB forum with an high quality and lightweight solution.
Existing users can link their accounts to Facebook in order to use the login functionality without having to create a fresh new account. Users and admins can also decide what informations should be imported ("synced") with their Facebook account every time they log in.
Many options are available, including an anti-spam measure to allow only verified Facebook accounts to register and an option to post a customizable message on the user's wall when he registers or links his account with Facebook.
The official documentation can be found here.
MyFacebook Connect is based upon Facebook SDK 3.2.3 and it's free as in freedom.