I don't want a semi-gov't authorized service like this. Because its existence means services would want to mandate it (even if they don't truly need it), and force users to identify themselves directly - may be even across services (by matching their email address, which now must be unique as it is identity-linked).
I personally sign up to all online services with a different email each. I would like to be sure that my identity is hidden behind an alias for all services, so that they cannot be linked together. And if i want multiple accounts (for better or worse), i should be able to achieve that end.