Jeremy Wagstaff of WSJ/Dow Jones called today, asking what this “tagging” thing is all about. Remember the 80’s? Tagging was something else entirely then. Par for the course for a new-school journalist, he interviewed me via Trillian from Indonesia, and asked if it was OK to blog about our conversation. That prompted me to revisit my blog, since I’ve been somewhat OTA for a while.

So when I went and logged into WordPress, I found a post that I had drafted a few months ago. I had already been writing about tagging and tag-centric views, and having just been down at the Technorati Hackathon I was musing about how trackback is an imperfect pivot for following conversations:

I posted last night about the hackathon, and linked to the wiki. Technorati shows only one other person linking to that URL — so where are all the hackers? Is looks like more people linked to Dave Sifry’s announcement page…. So, which URL to include in my post, so that it’s properly connected to the Technorati Cosmos?

This is of course quite relevant to the topic of the day. Trackback sucks because even though URLs are good unique identifiers, they don’t carry enough semantic weight to serve as useful pivots in information space. Technorati is a partial solution to the trackback problem, because even though it provides a central place (an anchor for pivoting on URL’s), if I’m writing about a topic and I want to link to other conversations on that topic, linking to one and only one URL that might have to do with that topic is both insufficient and cumbersome. By linking to the URL for the Technorati Hackathon Wiki or to Dave Sifry’s announcement of that event, I was asserting that my post was related to one or the other (or both) of those specific entities, thereby excluding reference to anything else.

On the other hand, if I include (as I did) a reference to a broader concept, such as my “technorati” tag, then I can easily pivot on that tag, linking to other entries [throughout the web] on that basis. That’s what I was writing about back in April of last year, that’s why I started calling my WordPress categories “tags”, and that’s why I pulled together blog entries and del.icio.us posts, and then eventually photo tags into a tag-centric navigation system on my blog. I’m sure I’m not the only one to have come up with this — but it does look a hell of a lot like Technorati’s tag aggregator.

So, what’s with all the hype? Tagging isn’t anything new — it’s just simple meta-data, applied in a flat (vs. hierarchical) namespace. It’s basically open source for information classification; the opposite of both the brute-force computational approach (”AI”), and the top-down, fewer-experts-know-best method (libraries, Yahoo in 1996). I’ve always thought that rigorous taxonomies are not “profitable” in terms of information management; they cost more to maintain than the value they add minus the error rate. It might be true that taxonomies can only be maintained successfully as public goods, e.g. the Dewey Decimal system, the domain name system, etc. Google leapt ahead by combining the machine approach with some of the benefits of the ‘Wisdom of Crowds’: PageRank. But this is still implicit/implied vs. declared data. That’s what it comes down to: can you reach a more accurate understanding of what something is about via interpretation of the content itself, or by examining the aggregate of what author(s), readers, and commentators declare?

I can also understand the point of view of those who think that it’s optimistic and naive to believe that aggregate amateur metadata is of real worth. I haven’t had to time to digest all of the discussion on the topic, and there’s probably something I’m missing in their criticism. But, my own experience — not just in blogging, but in application and data architecture in general, tells me that there is real value here. delicious is certainly a testament to that.

So it’s not technology — it’s the applications. For me, it was a combination of blogging and delicious that brought the utility of tags to the fore. Once I saw applications like Flickr and gmail using the same concept I began to think more about how to bulid further. I have a few more ideas on the topic; it should be interesting to see what happens over the next few weeks. I’ll try to keep more up to date, as “tagging” is clearly exploding.

In the meantime, let me be one of the first to cast a vote against the horrible, awkward term: folksonomy. Really, folks, we can come up with something better. We certainly should.