I don't agree that "microsoft already does this" - so don't take what I'm about to say to mean that. I mean only to show a piece of technology that more directly relates to the comments others have made.
That being said, Microsoft has developed a piece of technology called PhotoDNA[0], which is designed with the specific purpose of identifying child pornography. This is actively used on OneDrive and Bing, among other services - including Facebook. It's safe to say that OneDrive does not just delete the content if child pornography is detected - it reports to the authorities. Now, it's hard to argue that they don't have a right to do that, as long as the person is voluntarily using their services. That's where I draw a distinction here: Facebook could elect to turn on PhotoDNA on photos uploaded to their new service, and not properly educate their customers that stuff is being uploaded automatically. This does, essentially, constitute a passive surveillance system. Mind you, if it is used to establish that child pornography is found, you will have a hard time convincing most people that it is overstepping what Facebook should do. That's my concern - that this will be pushed as a "for the children" thing, and then extended to "to cut down on crime" later, once everyone stops caring about its existence.
That said, that's my concern. It's not necessarily what I think will happen. I have no reason as of yet to believe that it's the next step. I do not, however, want Facebook automatically uploading (or even scanning) my photos.
You're replying with a list of some of Microsoft's technologies that use face attribute estimation.
That's not what I was asking for. These are two very different things.