THE TERM METATAG

Let's stop using the term metatag. I think that there are several directions that we can go to make Drupal's node attributes make more sense. But first, we need to really understand what we're talking about when we say metatag.

A metatag is ONE single descriptive point in a document's larger description within a metadata framework like the Dublin Core (see link below). Metadata as it is commonly used today (e.g. in the Dublin Core Metadata Element Set) separates information about data into: 1) document descriptions (empirical data such as author, title, publisher, date of publication) and 2) knowledge descriptions (usually subject content and description/abstract). What Drupal attributes do is allow for the latter -- classification of nodes by subject. With this concept in mind there are a few directions we might go.

For more info on metadata elements see the Dublic Core Metadata Element Set

SUBJECT CLASSIFICATION

You can think in terms of what Libraries have historically done to get a sense of what is possible. A library catalog is a database holding bibliographic data (metadata) to help you find items in a large collection of data. You can do known item searching by looking for an author name, title, etc -- the document description stuff. But a lot of people want to find similar items, so maybe they find out what an item is about (subject) and browse for other books with the same subject. This is how most people want to use Drupal's attributes, I assume, and they may also want some sense of relationship (perhaps hierarchical, perhaps not) between each subject.