A new site jumps on the tagging bandwagon and actually ends up with useful search results. Why? Because it's narrowly focused on a specific topic and has a large degree of agreement among its user community.
For those of you who aren't familiar with tagging, it's simply the ability to annotate pages, images or other web content with descriptive keywords—you "tag" them with terms that supposedly help more precisely describe the page, in theory making it more "understandable" by search engines.
Tagging is a craze, but it's far from new. Meta tag standards for web pages were introduced way back in 1996, and other metadata standards for information retrieval date back to the 1970s. Considered alone, metadata can be a terrific thing, especially if it's created by a trained information professional using well-defined, standard terms (a "controlled vocabulary" in librarian parlance).
The problem with the web, of course, is that most web authors aren't trained information professionals nor do they use a controlled vocabulary when creating tags. Combine that with the subversive use of metadata by spammers to manipulate search engine rankings, and you know why search engines have virtually ignored metadata since day one.
Despite this unpromising history, tagging has exploded as a "new" way for users to annotate content and ostensibly improve the performance of search tools that take tags into account. Yahoo, in particular, has been a strong proponent of tagging, advocating its use in MyWeb, Flickr and elsewhere.
Tagging can in fact be useful for a service like Flickr (Yahoo's photo sharing service) because images are inherently difficult for a search engine to index. Even a few words associated with an image can help it get found far more easily than if it's only identified by a filename. But the lack of controlled vocabulary or agreement on meaning of words among users can also lead to virtually worthless search results.
I have yet to see an example of a generalist site that uses tagging (search engine, social bookmarks, etc) that has impressed me with its use of tags in refining or enhancing search. But tagging can work, especially when applied by a relatively homogenous community to a narrow subject. End of rant—here's a look at a site where tagging actually works fairly well.
Millions of Games
Millions of Games is just what it suggests: A search tool for finding all manner of games on the internet. What makes it different from other similar sites is that users are encouraged to tag games (this is called "mogging" a game). And with Millions of Games, most of the heavy-lifting for creating tags has already been done by the developers of the site.
The site uses controlled vocabulary (called "Gameology") to describe categories (arcade, shooter, puzzle, etc). Although you can also add your own free-form tags, these category tags are well known to most users, so there's little ambiguity about what the tags mean.
Millions of games also measures popularity, both user rankings (from one to five stars) and how frequently a game is played.
And like other community sites that use tagging, Millions of Games allows you to see information about other users that you might find helpful. If someone rated or mogged a game you like, you can see other games they've mogged, as well as other games they've played, and how often. This is a good "peripheral" way of finding new games based on the tastes and behavior of others.
Tagging on Millions of Games isn't perfect, but in general it does seem to work better than other services that aren't as narrowly focused. And the extra information you get on each game, like ratings, the number of people who have mogged a game, its thumbnail image and so on lead to an overall quite good search experience (not to mention a lot of fun new ways to waste time, if you're into gaming).
For tagging to succeed in the way that its proponents envision, this "less is more" approach offers a lot of advantages. Rather than allowing users to tag anything with any words they fancy, adding structure, defining a mutually agreeable taxonomy and relying less on idiosyncratic language seems like a very promising approach. Millions of Games is an example of a good start to a more useful form of "structured tagging."
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