Glad to hear the advice above helped to get you going in the right direction.
As for posting to Facebook, yes, if they make the post public, it will go to Facebook as well (if you have it configured that way in JFBConnect). If the post is public, it means that search engines and other things will be able to scan and see it already, so pushing it to Facebook generally isn't a problem. It's up to you, as the admin, to determine if your users posts would be relevant to a more general audience in Facebook.
I hope that helps answer your questions,
Alex