Very simply the lists are just that, lists. Lists of movies, tv shows, books, songs etc. All of which you can get from iTunes and its myriad of stores.
Some of these lists will be about a subject, some about a person. Some of the lists will contain things that are not yet released (but are up for pre order), some might contain things that were available at the time the list was created but now aren't. All lists are focused on the US for the moment so sometimes there might be things a visitor from outside of the US can't get, our apologies on that one.
Some lists are serious, some silly. But hopefully you'll find something to enjoy in them.