Goetz,
The Profiles page lists all text-type and date fields that you've created within JomSocial. On the left-hand side, you'll see the JomSocial field name. On the right hand side, you'll see a drop-down selection box. This drop-down gives the information about the different user profile information that's available to import from Facebook, like "User - First Name" or "Basic Info - Hometown City". Once you set the drop-down, JFBConnect will try to automatically import that data when the user registers (and logs in, if the "Import Always" setting is enabled).
We don't have a comprehensive guide as to what field is available to import and where it can be found within Facebook. They are constantly changing their layouts, where profile information is input and displayed, and different parts of the world also have different layouts for user profiles, which makes it impossible to display 'where' the data comes from.
Hopefully, the description for each field is clear enough. The page below lists all fields that were import-able from Facebook for the 4.1 release. They changed a little for the 4.2 release, but the list below is pretty accurate:
www.sourcecoast.com/jfbconnect/features/...le-import-for-joomla
Hope that helps, but if you still need clarification, just let me know,
Alex