Online identities of today are just a bundle of information submitted by a person, stored somewhere, and protected somehow, typically with just password. You can get free email accounts and use that to sign up anywhere claiming to be anyone. Not only you but anyone with the password can as long as they are polite enough to restore changes they made before you notice.
And what does all the new identiy technologies do about this problem? Basically nothing. But they are great for efficiently sharing untrustworthy data among interested parties so the user don't have to deal with countless passwords and forms. What do the identity services get out of it? They get to lord over that pile of untrustworthy data. Fantastic.
What I find really amazing is that all that keeps this house of cards from flopping is: honesty.
IMHO, the missing piece in online identity is identity sponsorship by businesses based on transaction history. They are like little boyscout patches except they are issued by everyday businesses with which the user had extensive business with. The user's identity is the shirt onto which those patches are sewn into.
For example, Bank of America or BlockBuster could issue me a patch that I've been their customer for more than a decade. They can do it to retain customers or as a new source of revenue. There is no privacy issue either since the patch could just be a set of numbers, each representing a trust vector.
Hmm. We need a fancy term for this. How about Trust Syndication?