> Much more can be said about pros/cons and naming. I 
> personally, after getting used to it, have found it rather 
> convenient to use http URLs and it saved me many headaches of 
> having to think of yet another naming convention.

I resisted "http" in namespaces for a long time because the "p" stands for
"protocol" and this gives the misleading impression that some network
communication is involved. But I know when I've lost a fight, and I now go
along with the flow. It's stupid, but you get used to it.

Historically, there has always been a camp that believed that namespace URIs
should in fact identify a resource, for example a RDDL document. In fact,
namespaces allocated by W3C do (by convention) always identify a document
that gives you a description of the namespace and a pointer to its
specification.

Michael Kay
http://www.saxonica.com/