1. We can lie. My occupation according to Facebook? Systems administrator at Aperture Laboratories. Likewise, I don't have my address, phone number, or real e-mail address listed. My gender, political leanings and sexual identity are listed, but these aren't things I even consider private. Everyone I know knows these things, including people who don't know me very well at all. It would be a problem if I lived in Iran, but suffice to say that if I did, I would just lie about them. This makes Facebook a particularly unreliable source for information about things the state wants to suppress, don't you think?
2. "Data on smartphones shows how peoples' weight loss plans or even how many push ups they make every day," he added. So? How is that information going to be useful to anyone at all? One of my friends on the other hand, is what the police here refer to as a "Code 3", which means he can kill people with his bare hands or any nearby object that could serve as a weapon. He's also known to be a little, um, twitchy. Which is something that *is* useful to police, and it *is* recorded by them, in no small part because there have been incidents where the police have been involved. They write that stuff down, you know.
3. The supermarket has records about how much KD I buy and how much toilet paper I buy, which, while being highly personal, is again, useless to anyone besides the supermarket. It's highly unlikely that my insurance company will ever get this information, and you could just as easily glean it from my garbage anyway, which requires no specialized knowledge.
4. The current public attitude about Facebook is that if you want it to be private, don't put it on Facebook. Personally, I don't have much of a problem with the public knowing what the route I bike is, and how fast I bike it. Some stalker might find it vaguely useful, but since I'm male and I don't make a habit of pissing people off, I don't see that as particularly dangerous.
5. If, for any reason I decided that I would prefer not to be found, Facebook makes this particularly easy. I can change my name. birthday, address and gender on a whim, and I could feed it information that is completely ridiculous. I could stop using applications that track my whereabouts (there's only one anyway). I could change my bike route (which is necessary at my level of fitness anyway). Again, this makes Facebook a really unreliable method of getting personal information, if any such information exists on Facebook to begin with.