Mark Andreesen weighs in with his explanation of OpenSocial.

Basically sounds like you can register a callback with the YASNS which pulls HTML / javascript from your server. Sounds very good and simple as a way of embedding your application into their pages. Great! But not much of a clue what it means for whether your application can get access to the social network itself. Or to what extent.

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 ...)