They're only doing the right thing for them, this move seems to incidentally benefits users too but not really. it prevent outcomes such as users 1) closing their account / switching to another website 2) creating an additional fake profile only for work.

This article [1] is imho quite right, this is mostly a non-issue turned into PR.

1:http://rexriepe.com/2012/clever-pr-facebook-bends-a-non-stor...