This list shows who is responsible for each channel in TV-Browser. Besides this list there are some plugins that get data from other sources. For details see here. There you find plugins that grab data from a VDR, from other devices (e.g. Dreambox) or other applications.
Missing a channel? You want to offer a channel yourselfs? If yes, please read this article.
For RTL, Pro7 and a few other german stations we don't offer descriptions for every show due to a licensing issue with VG Media.