Does Facebook really have a unique amount of data? Google also knows a lot about people through billions of searches a day. Apple can learn a lot through people's iDevices, and Google (again) or Samsung can do the same with Android. So can any cellular service provider, or anyone running coax or fiber into your home. The government can tap any or all of those. At least Facebook doesn't have an army, or paramilitaries like DHS or just about any sheriff's department I've ever encountered.
I'm not saying the author's concerns are invalid. I've had occasion to think about these exact issues a lot, and I'm sure many of my soon-to-be colleagues have too. The way I see it, Facebook and other social media occupy much the same position as phone companies used to, both in terms of how they facilitate interaction and in their privileged financial/infrastructural positions they occupy. There's good in that (e.g. ability to pursue the kinds of speculative projects that Bell Labs was famous for). There are also dangers, no question.
The thing is, if it wasn't Facebook it would be someone else. There's no shortage of others ready to step in if Facebook alone were targeted with laws and regulations. Instead of worrying about Facebook specifically, we need to think about what a modern "common carrier" law should look like in the social-media age. Perhaps some kinds of regulations on use of information do make sense, but that dialog isn't likely to be very constructive so long as most of the people on one side seem to be free-market fundamentalists betraying their own principles by singling out one company among many.