URI as Identity (was Re: JRD, XRD Re: Webfinger)

The area of digital identity is /huge/. There are many, many different 
schemes and mechanisms, competing and interoperable.

It is not in our charter to crown one as victor, nor to invent a new 
contestant.

We can and should use URIs for identity.

Discovery mechanisms for those identities are up to the different 
identity standards or identity providers. Clients will need to 
understand those mechanisms and use them.

That's pushing some work onto client developers.

-Evan

P.S. I sketched out pseudo-code for handling identity URIs with http: 
and acct: protocols; see here:

https://www.w3.org/wiki/Socialwg/Social_API/Identity_to_API_endpoints

This is based on my experience with pump.io and StatusNet. I think it's 
a relatively robust mechanism that covers most identity types we'll run 
into. There's probably some extra handling for types like Turtle or 
RDF/XML that could be added there.