It's astonishing how many people will post pictures of themselves getting ready to leave for vacation and neglect to remove the GPS data from them - make sit super simple for any burglar to know when you'll be gone and where you live. Yes, FB is one place where that happens a lot, but it happens on all the others, too.
As for the "gummint" using private security cameras in a big conspiracy - nope won't fly. I was a police administrator for years and I know who does and doesn't do that sort of thing. Our government isn't one of them to any degree - yet. It will ultimately happen, though not as a conspiracy, but like Great Britain does for policing and domestic security. A number of Interpol nations do use facial recognition software in conjunction with public and private security cameras to try to identify wanted terrorists and the like, but there are limits to what can be done with the typical low-resolution images from most private CCTV images. High-res cameras like those used for public safety operations are a different matter. It's amazing how well some of the FR algorithms can work, given sufficiently detailed images.
In the US it is more likely that you'll see limited tracking of individuals through RFID chips in drivers' licenses, credit cards and the like. There are already companies trying to peddle systems using RFID transceivers mounted in traffic signals to track people, but the number-crunching requirements are pretty huge still, and virtually all the people I've talked with are wary of it due to political considerations. Tough to get that one accepted by the public. They will get it done one of these days, though. 1984 may have come and gone largely unnoticed, but Orwell's vision is steadily coming to pass as people allow legislators to increasingly encroach on the Constitution. But FB funded by the FBI and CIA for domestic spying? Don't be gullible! Though at the rate FB share prices are plunging from their IPO price, you could easily think the government was involved - nobody else loses money as fast as our gummint. (grin)
I am no longer surprised much by the silly stuff the people will read on the internet and wholeheartedly swallow. The goofy conspiracy theories out there are myriad and bizarre. No one who has ever chaired a committee could believe that that many people could be involved in a conspiracy and have it even vaguely resemble functional. Two people can keep a secret - if one of them is dead. Two hundred or two thousand? It is to laugh. To make one actually function with more than a few people involved beggars the imagination.