Shelley Powers came up with an interesting alternative to trackback: “tagback,” in which she creates a unique tag (in the folksonomy/flickr/del.icio.us/technorati sense of the term “tag,” not the XML sense) for each weblog posting, tags the posting with that tag using Technorati’s syntax, and then encourages anyone commenting on the entry (as I will once this is live) to tag their comment with the same tag. So, for example, her first post has the tag bbintroducingtagback, and the Technorati URL http://technorati.com/tag/bbintroducingtagback links to her posting and the comments on it. This way, you don’t have to rely on trackback or comment software on her weblog—two processes getting more polluted by spam lately—to create a connection from her entry to yours.
Her posting does have a lot of comments, and it’s an interesting exchange. (It’s now closed to comments, but here I am commenting, which shows another strength of her new idea.) Some complain that a single, oddly-spelled unique tag is contrary to the classification that they see these tags playing, but I disagree. Tags are metadata, and much of the fun of metadata is the creation of new kinds of applications around existing metadata or metadata systems, and that’s what Shelly’s done.
Others quibble with her plan to prefix her tagback tags with bb (as in burningbird.net) to identify them as part of her tagback namespace. They ask what would happen if boingboing did the same thing—as if a website co-led by Mr. Metacrap himself would add something as useless as metadata to their entries. Shelley replies that, because the tag incorporates the piece’s title (”Introducing Tagback”), another piece with the same tag would probably be related, so this namespace collision wouldn’t necessarily be such a bad thing. And, when creating a new tag, a programmatic check to see if a given tag has already been used is simple enough.
This is a nice way to create and use indirect links on the web. While I’m not quite creating a link from her weblog entry to my own, her page’s inclusion of a link to a Technorati query for the page’s unique tag and my ability to tag my entry with the same tag in del.icio.us means that I’m creating something that her page links to, so I get the same effect. A difficulty with implementing indirect links has always been the infrastructure to implement the indirection, and Shelley noticed that Technorati could serve as this infrastructure. (Experiments with backlinking have also used Google for indirect linking infrastructure.) To paraphrase something I said above, it’s nice to see someone create a new linking application around a new class of metadata so quickly after it appears.