FB share & like works fully for joomla posts but doesn't appear in Jomsocial & Kunena.
FB commenting appears after each blog article but doesn't appear in Jomsocial & Kunena.
JFBConnect doesn't automatically add the sharing buttons or comment boxes to JomSocial and Kunena. We have modules or our easy-tags which can let you decide how and where to place those features in any 3rd party extension though. For example, you can use the module in a position that exists on your Forum or add the following to the Kunena template files wherever you want the Facebook Like button to appear:
There's a ton of Easy-Tags we support for all of our features which you can find a list of in the JFBConnect -> Social -> Easy Tags area in the admin section of your site. There's also a corresponding feature in the SCSocialWidget module that you can configure as well.
I hope that helps explain,
Alex