peer-to-peer schema models: "Users, not designers, create and communicate meaning."

Does anyone know of current peer-to-peer RDF projects?

By this I am referring to projects where the RDF metacontent or schema 
is defined over time by users.
(some people might consider the CD labelling project of this type.)

I've proposed this model for a number of projects including:
The WWAAC concept coding framework project
The CEN metadata for accessibility  project

There may well be significant hurdles in adopting this approach, 
however was inspired to request evidence of current successes by the 
excellent: "Where the Action Is"  The foundations of embodied 
interaction by Paul Dourish.
when after a particularly intractable and rambling passage he announces:

"Principle: Users, not designers, create and communicate meaning."

regards

Jonathan Chetwynd
http://www.peepo.co.uk     "It's easy to use"
irc://freenode/accessibility