My curiosity hovers over how much freedom FB app developers have in the "Request for Special Permissions" dialog.

Will the FB API force them to disclose the fact their app wants to email you directly, as is shown in the screencap, or could this fact be obscured with clever word choice or some other diversion in the dialogs?

If the latter, then this new feature sits somewhere close to sanctioned phishing. Once an untrusted 3rd party has your email address, FB can't revoke it. The recent stories about Farmville don't give me much reason to trust such 3rd parties.

Indeed at that point, FB, along with whatever role FB had hoped to play in data-mining the traffic it sends to your address, become entirely irrelevant.

Which begs the question: why does FB chose to cast itself as the easily expendable middleman?