JFBConnect with JomSocial 3.x. What does JFBConnect add?

A lot. If you haven't already, check out our JomSocial Features page, which has a video and more information. The main things are:
* Google+ authentication
* Customizable profile import - You can select which fields from Facebook and Google are imported into any of your JomSocial text-type fields
* Cover photo import from Facebook and Google+
* Open Graph Tags and Actions for JomSocial
* Enhanced Activity Stream integration

Those are just the features specific to JomSocial. JFBConnect also has social buttons for all of your content, Facebook Invitations your users can send to their friends, and lots of other integration outside of JomSocial.

I hope that helps, but if you have any specifics you're looking for, just let me know.

Thanks,
Alex