Stan wrote:

Syntaxwise, I like [[meta:name:value]], with a general inclination to create new names that are recognized specially, so I can say [[category:person]] or even [[cat:person]] to be really brief, since nearly all articles will have one or more category tags.

"meta:" is already used as an interwiki link syntax to get to Meta-Wikimedia. However a metadata:namepace would be a great place to put category tags and inter-language links. For example [[metadata:United Kingdom]] would be where all the category tags and language links for [[United Kingdom]] would go.

As it is, all these metadata are (or will be in the case of category tags) placed in the article itself resulting in cluttered harder to edit wiki text. It might also be easier to do relations between articles and even make it possible to place interlanguage links in once and have all the corresponding metadata pages on other language wikis update at the same time.

Just brainstorming....

-- Daniel Mayer (aka mav)