I think that I disagree (that this is a counterexample); it shows that people want a 'one-stop' identity solution, but not that they trust Facebook to keep their identity private.

But the statement to which I was replying is "the problem is that ... no one would trust them". The popularity of "Sign In with Facebook" belies that it's a problem to not be trusted (at least when it comes to offering identity services).

Ah, I see. I was implicitly assuming that the parent's other requirement:

> different pseudonyms available that __don't reveal your 'true' ID or other pseudonyms to the site owner__

(which isn't offered by Facebook—right?—and which does require trust in the issuer) would be part of the putative Google Identity.

On the other hand, having spent this much time arguing that it wouldn't happen, I'm now wondering why OpenID with Google as 'vouching agent' (or whatever that part is called) doesn't count.