So Facebook Chess is now hosted at chess.com - despite it being a buggy application, about 45,000 games have been started, and all kinds of chess players networked.
Chess addictions across the world have been renewed as yet another way to procrastinate on Facebook has been invented!
Of course, the old Correspondence-cookie comes up. How do I know that my opponent isn't just loading my moves into Fritz non-stop? One friend I'm playing seems to be playing a lot better than he always used to OTB. And unlike on chess.com where most people (from what I can see) sign up in order to improve their game, not cheat, Facebook is more about one-upmanship.
This keeps sites like chess.com in business, whilst feeding the site with the new, keen-to-learn blood.