I think we really need to see how the identity is managed in real world and may be that can help us figuring out how it may work in digital world. So we would need a passport like mechanism, which would assert very basic information about the person across the international boundary and that is where I think we may concentrate at these international conference (any thing beyond that would be equivalent to boiling the ocean). Then we would need trusted bodies for various context. For example the international transactions would need banks working as intermediatery (as used for trade by companies across international boundaries) and then you may have technical bodies like medical bodies who may vouch for their members in transactions. So, I agree with the basic idea that there would be large number of bodies and also think that there would be multiple protocols that would be developed for and by each of community as they need to share this information. I think the idea of having a single standard across the board is a dream.
We have to remember that the identity is not some thing like internet which was developed completely from scratch and hence the people who joined later accepted the work of the earlier groups. Neither is it like the desktop technologies which were accepted easily due to prevelance of single OS.
That's why we should not expect a single protocol or even "meta-identity" system to be accepted by the world because paradigms have changed or are changing in the digital world.