Mark Andreesen weighs in with his explanation of OpenSocial.
What he does say is that apps. can (are likely to) test which YASN they're in and run differently in each. So, er, yeah ... OpenSocial doesn't prevent apps. taking advantage of YASN-specific stuff.
So it's kind of what I expected ... but let's see ...
(Drumming his fingers impatiently ...)
3 hours ago