Tim Bray on Technorati Tags: “I’ve spent a lot of time thinking about metadata and have written on the subject; the most important conclusion was: There is no cheap metadata. I haven’t seen anything to make me change my mind. …I think that it would be nice if a huge number of web pages converged on using a simple, flat, shared set of tags…” I think that’s called a controlled vocabulary.

And he sees the downside of free-for-all tags: “…if I do a tag search for “Microsoft”, and if Robert Scoble or Jonathan Schwartz have posted on the subject any time in the last 48 hours, I want those at the top of the damn list, not what some college kid wrote three hours ago.”

One conclusion he reaches, as I have, is that there should be a balance: “I suspect Technorati, and anyone else who takes this up, should offer an (optional) “scheme” field in their tag search capability, which would be handy for those who care and invisible for those who don’t.”

I can’t help but feel we’re reinventing the keyword metatag, a place where the user could put her own keywords in to tag her content, circa 1995. In that case it started out useless, then became useful, then it was abused, then made useless (as control was re-centralized). There’s a lesson there.