Using SKOS for representing Drupal taxonomy vocabularies and terms

Hi,

As you might already know, Drupal 7 will expose its data as RDFa and we've
tried to represent Drupal's internal structure in RDF. The current status of
the schema is depicted in the graph at [1]. We received a comment at [2]
recommending to use skos:ConceptScheme instead of skos:Collection for
vocabularies. This seems a fair point, and I would like to get some feedback
from the SKOS community before I make this change, as there might other
things we've missed. The main concepts we have in Drupal are taxonomy
vocabularies and terms. Each term belong to one vocabulary. So far we've
mapped 'term' to skos:Concept, and I think that's fine. We've mapped
'vocabulary' to skos:Collection but the suggested change is to use
skos:ConceptScheme instead, which would also imply to use skos:inScheme
between each term and the vocabulary it belongs to. Below are some examples
using a vocabulary for 'countries' and a term for 'Italy'.

With the current RDF representation:

site:vocabularyCountries a skos:Collection .
    skos:member site:termItaly.
site:termItaly a skos:Concept .


With the proposed change:

site:vocabularyCountries a skos:ConceptScheme .
site:termItaly a skos:Concept ;
    skos:inScheme site:vocabularyCountries .


And with all the other metadata for vocabulary and term:

site:vocabularyCountries a skos:ConceptScheme ;
    rdfs:label "Countries" ;
    rdfs:comment "A vocabulary containing countries on a Drupal site" .
site:termItaly a skos:Concept ;
    skos:prefLabel "Italy" ;
    skos:definition "A term for Italy in a Drupal site" ;
    skos:inScheme site:vocabularyCountries .


I would appreciate any feedback on whether this is the best way of using
SKOS in the context of Drupal taxonomies [3].

all the best,
Steph.

[1]
http://openspring.net/blog/2010/01/12/rdfa-in-drupal-7-last-call-for-feedback-before-alpha-release
[2] http://groups.drupal.org/node/44094#comment-154828
[3] http://drupal.org/handbook/modules/taxonomy