Sounds like Microsoft joining the web standards committee, at least in Facebook's case. They have no incentive whatsoever to make the data on their servers portable.
That's precisely what I was thinking. Until I see an actual implementation, I'm assuming this is just a token gesture.
Yup, if I was Facebook, I would join the Workgroup too if only to keep track of or keep good relations with a group that may affect my business. The article seems to exaggerate the importance of the move though.
If I were Microsoft, I'd try to come up with some way to get Passport (aka Windows Live ID) into to the data portability effort.