I was reading on some page from some clever speaker about the URN being dead
once and for all.   Then in the new beta release of the InstantReality X3D
and superset browser, there is this:

"Networking component

This component defines the node types and other features used to access
file-based and streaming resources on the World Wide Web. (Higher levels of
this component extend the URL support of a browser, such as supporting URNs
(Uniform Resource Name), which are a superset of the URL concept. A URN
allows an abstract resolution mechanism to be invoked to locate a resource.
This allows a resource to be located on the local machine or a platform
dependent resource to be located using the URN along with platform-specific
identifiers.) "

Someone finds a use.

http://www.instantreality.org/home/

The 3D thing is gaining speed.  The node set being supported in that public
beta is incredible, physics too.  I think the pundits may be right: Web 2.0
may be the shortest version of the web so far.  It's moving pretty quickly
to Web 3.0.   Faster and faster... the hallmark of feedback-mediated
adaptation on networks.

len