With this concept you can get OCS syndicate news or you can get only the changed OCS news.
With this concept you can get OPML syndicate news or you can get only the changed OPML news.
With this concept you can get RSS syndicate news (versions: 0.91, 0.92, 0.93, 1.0) or you can get only the changed news.
With this concept you can get ScriptingNews from syndicates or you can get only the changes.