GuideHound EPG is designed to take an input source with a relatively small amount of information in it and create the best media center experience possible out of it. Of course, how successful this procedure is depends on your source.
A gross simplification, but essentially GuideHound EPG cares about one thing: Is it a movie or a TV series? If it is a movie, we can look up a movie cover on http://www.themoviedb.org, add the movie to Media Center's Movie Library and try and import cast and crew, etc. If it is a TV series, we can look up a series cover on http://thetvdb.com, enable the "record all" functionality, etc.
There are a few ways that we can go about determining the type of entry. Some sources have categories data where they mark the entry as being of category "series", "movie" or "news", etc. If your source has this information, you can use the Category Mapping function of GuideHound EPG to treat the entry as the type you want. GuideHound EPG does not actually import the categories in the source into Media Center as actual Media Center categories - rather it uses then to determine the type of entry. The category list is created when you set up your sources.
If you are not so lucky to have category information in your source, you can still use the Category Detection functionality to look for keywords in the title of the entry and map to a category.
There are other detection methods in progress and this will change as new sources appear and start to provide data in new formats.