Technorati, a site that indexes 4.5 million weblogs, is now enabling us to sort blog posts by tag. This is way way cool. In fact, it marks a next step in the rapid evolution of the tagging economy. [Disclosure: I am on Technorati’s Board of Advisors. But I would have been excited about this anyway.]

The tags come from three sources. First, if you’ve uploaded a photo to Flickr and have tagged it (or if one of your pals has tagged it), it will show up under that tag at technorati. Second, if you’ve bookmarked a page using del.icio.us, it will show up under that tag at technorati. Third, if your blogging software supports categories, your blog posts will show up under the categories you’ve assigned; categories are now tags in the eyes of Technorati.

Even if your blogging software doesn’t know from categories, you can still tag a post with, say, “weasels” by inserting into it the following line:

It’s easy to imagine this becoming a standard part of the footer of blog entries.

Take a look at this page to see how Technorati aggregates all the blogs, flickr photos and del.icio.us bookmarks tagged as “humor.” This page shows the top 100 or so (I didn’t count) tags in alphabetical order, with font size representing the number of tagged items.

This is exciting to me not only because it’s useful but because it marks a needed advance in how we get value from tags. Thanks to del.icio.us and then flickr in particular, hundreds of thousands of people have been introduced to bottom-up tagging: Just slap a tag on something and now its value becomes social, not individual. As these tags are added willy-nilly, two issues arise: We want to get more value from them and we want to work out the scaling problems — it’s one thing when there are 30 things tagged with “weasels” and another when there are 300,000. A site like technorati, which already gets its value as an aggregator, is in a good position to innovate around both issues.

Now for some observations and guesses.

First, categories are not tags. I’m guessing that the average number of categories used by any single blogger is in the 3-15 range. Many of us want to keep our categories broad because they are intended to help a reader see all of our posts, and we want to be inclusive rather than fine-grained. If that’s the case, then tags commonly used by categories are not going to be very useful when aggregated by Technorati. Actually, they might be useful to researchers but not very useful to casual readers. That’s not a criticism; I’m glad Technorati is treating categories as tags. But I suspect that the hand-tagged tags are going to turn out to be more useful because we’ll hand-tag them with their aggregation by Technorati in mind. (Bogus Contest: How many hours before some posts a bookmarklet to ease the hand-tagging of multiple tags?)

Second, it will be fascinating to watch the social effects as people adjust their tag sets in order to get aggregated either into the most popular tags or to be segmented into smaller groupings. That is, if you want to be found when people are searching for blogs about America, you will learn to tag it with (say) “USA” and not “U.S.A.”, “US,” or “America.” And if you want to have your posts be found by people searching for posts written by members of your Dungeons & Dragon’s group, your group will make up a tag that no one else would use. How this sort of stuff occurs at Technorati depends to a large degree — but not entirely — on how Technorati chooses to enhance the system. Little changes will have rippling effects.

Third, this represents the externalization of tagging. That is, Technorati is a broker of tags, not a place where you create tags. There are other important functions that could be handled externally, including the creation of thesauruses so that items tagged as “USA” get clustered with ones tagged “America” and “Etats-Unis.” The particular apps where you tag stuff can, of course, compile their own thesaursi. And, they’re likely to be compiled automatically by noticing the different tags that are applied to the same item. But having a thesaurus compiled from a superset would help smaller-scale apps cluster tagged items well and would provide additional useful information to all clustering apps. Local thesauri are always going to contain the most valuable information, but info from the aggregated thesaurus can also help. But, there will be social effects from having external thesauri. I don’t know what those effects will be, but I suspect that they’ll be significant since thesauri are about meaning across groups differentiated by meaning.

Fourth, why can’t I subscribe at Technorati to an RSS feed for a particular tag? [Note: Dave Sifry tells me that RSS and API support are coming soon; they wanted to get the release out faster rather than completer.]

Fifth, Yay! This is a big day for tagging.

My first technorati tags: Technorati tags taxonomy

Categories: Uncategorized dw