[PROPOSAL] Separate Public Identifier from IdP Identifier

[Martin Atkins]

Currently the conceptual model is that each user has a "public" (that 
is, presented to RPs) identifier, but can optionally create additional 
identifiers which "delegate" to the real identifier. The delegate 
functionality has several purposes, including:
  * "Vanity" identifiers on personal domains while letting someone else 
do the hard work in running the IdP.
  * Ability to switch IdPs without losing identity

However, experience has shown that the above model is often difficult to 
grasp for those new to OpenID. This proposal is really just a set of 
terminology changes and an alternative conceptual model that aim to make 
the delegate functionality easier to understand. It does not change the 
mechanism of delegation at all, though it does change the discovery 
protocol.

I've placed the full proposal on the OpenID wiki:
     <http://www.lifewiki.net/openid/SeparateIdentifierFromIdPToken>