Best practice for expressing tags/metadata in URLs (openurl-like)?

We are testing out Google's CSE and it has the option to "categorize"
links based on patterns inside the URLs.

For example: you can tell google to tag URLs with a ".com" as
"Commercial". Or URLs with a "/2008/" in them as "Date: 2008" (for
example, archived Blog posts have this sort of format).

Which, got me to think... what should we expose in the URLs that link to
a record in an NGC?
  * The title?
  * The author?
  * The year-published?
  * Subject headings?
  * LCC cluster (like the HILCC; for example items between RC321 - RC
429.99 might get auto-tagged  internally as "Medicine > Neurology"
(HILCC id #1336), but what would the URL look like? Would the URL have
the internal HILCC (1336) or something like "[HILCC]Medicine|Neurology"

For example, such a URL might look like this:


http://mycatalog.net/biblio/type=book/subject=hilcc:1336|medicine|neurology/title=Principles-of-neural-science/year=2001

So, should permalinks in an NGC look like?
--
_________________ ___ _ _ _ _ _ _ _
*Ing. Alejandro Garza González*
Director, Tecnología e Innovación, Biblioteca
Tecnológico de Monterrey, Campus Monterrey

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Enlace Intercampus: 80 689 4037
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