For the unintiated, tags are simply keywords that are applied to something. On the Internet, they’ve been implemented as a way for users to supply their own metadata to online resources. Yahoo! is using tags in their My Web service; bloggers provide tags on their own blogs which Technorati then mines; social bookmarking services such as Furl and del.icio.us allow users to organize their bookmarks using tags; and Flickr users tag their online photo galleries.
Newzingo is doing basically the same thing, except its source of "tags" is from Google News and not individuals. Regardless of the technology under the hood, Newzingo is a fascinating glimpse into what journalists world-wide are covering.
Be sure to check out Newzingo’s sister site, Techzingo, which–you got it–does the same thing for tech stories and, my favorite, Buzzingo, which tracks propular search items using Yahoo’s Buzz Index and Google’s I’m Feeling Lucky.