Google seems to be maintaining a certain aloofness don't they?
The phrase 'OpenID Provider may use your email address to personalize your experience on their website' is interesting. Is this an actual restriction that Google has placed on the app creators (or one they committed to) as to how the app can use my email address, i.e. for personalization only?
If so, it would preclude them from releasing the address in response to an OpenID sreg request.