I think this is facebook getting scared of regulation and so thinking that if facebook's "features" get adopted more so, then they can be pinpointed by authorities less. My thoughts only.
This announcement comes just days after FB hired a crack team of anti-trust defense lawyers, of course it's a move to defend against potential regulation/litigation. I'm not saying their defense team caused this change either, just that there this fits a pattern that shows FB's leadership is very concerned about potential government action against them.
To whatever degree that's true, I would assume it's to get some momentum of support -- dependency if you will -- generated to peel off some of the people who would just as soon see FB go the way of Friendster. Purely usage juicing.
