place time person etc, first degree concepts for faceted search, (these may have display formats (person shows avatar, place shows map etc), metadata aspects (lat/long, gmt+/-, name) search result display formats (timeline, map w points, social graph) etc associated with them)
extensible with: domain specific ontologies, 2nd degree concepts meta objects, 3rd degree concepts (non relational classification with metadata aspect attached, rich proto ontologies in formation) defined tags (tags with defined meanings, loosely semantic tags) dumb tags (grouping functions)
extensible with:
domain specific ontologies, 2nd degree concepts
meta objects, 3rd degree concepts (non relational classification with metadata aspect attached, rich proto ontologies in formation)
defined tags (tags with defined meanings, loosely semantic tags)
dumb tags (grouping functions)