There's a ton of information you can get from the different social networks. Basically, all of the public user information is available from Facebook, Google+, Twitter and LinkedIn. That includes name, location (city and country), hometown, education, interests and much more.
Each network doesn't obviously have all that information.. like Twitter, which doesn't have a way to add your education, but both Google, LinkedIn and Facebook can provide that.
Some caveats are that Twitter will not provide the user's email address. You can import their other profile information, but JFBConnect will present a mini-form to ask the user their email address in that case.
Likes can be obtained from Facebook, but it's not something JFBConnect does directly. Likes is a very open ended result, which means you'd need to have something meant to parse out that data. JFBConnect has an API that makes it easy to get that information, but you'd need a developer to help implement it if you wanted to store all of the user's public Likes.
With Facebook, they do have different categories of interests for movies, books, religion and other data which JFBConnect can import into your database or 3rd party profile extension.
I hope that helps explain. If you have any other questions though, just let me know.
Thanks,
Alex