Dig a little deeper and some of this soul-scrying voodoo becomes slightly less terrifying. One of the TV-show likes that's a predictor of female homosexuality is The L Word  – a drama about lesbians. Two of the pages associated with being a gay man are Wicked the Musical  (no comment) and the No H8 campaign , which advocates equal marriage. I'm sure you could guess my gender from my self-declared love of Jane Austen and the history of fashion on Facebook. Or you could just look at my name.
But there's a bigger reason why we oughtn't be that concerned: who the hell clicks "like" anymore?
Facebook is designed to be used in a way that corresponds with the actual use patterns of fewer and fewer of its members. Even "active users"—its new preferred metric, since the total number of registered users is now limited by the population of the earth—may not be active the way it likes us to be.
The perfect Facebook user checks in whenever they go somewhere; they like the pages of all their favourite bands, movies, TV shows, and even their dentist; they tell Facebook where they work and went to school; they visit other sites through apps on Facebook; and they never, ever change their privacy settings from the default.
Does that describe you? Does that describe anyone?
The fact is that for an increasing number of people Facebook is basically a glorified webmail service. There's still a lot of money to be made in that—targeted ads served against keywords culled from your messages and events is the reason why Google runs Gmail, for instance—but not enough to justify Facebook's market cap, and certainly not as much as Mark Zuckerberg would like.
The company's been big at giving users new ways to get data out of Facebook, such as redesigning its news feed and introducing Graph Search; but it has yet to touch on any changes which would make people more likely to put data in. As Buzzfeed's John Herrman writes , Facebook "is demanding more and more of a graph that is able to provide less and less."
The real problem we all face isn't that the information we put out on the internet might be used against us. Despite looking like it was going to be ubiquitous, the fad for documenting every aspect of one's life is dying off. Foursquare has pivoted to be about providing data, rather than encouraging check-ins; Instagram, which provides ephemeral, context-free images, was poised to overtake Facebook as the leading photo service on line (until it became Facebook); and when was the last time you "liked" something?
We don't have to worry about what we put out on purpose; the problem is what we put out without knowing. It's not scary if Facebook can tell you're gay because you choose to like certain pages; it's more concerning that Google can tell your age because of your search habits; and it's downright worrying that Target can find out a teenage girl is pregnant before her own father based on what she buys .
If you choose what data to share, you are probably not too concerned about the inferences that can be drawn from it. But very little of what we share is done voluntarily these days; and as Facebook struggles to get us to give it the information it wants, they too may start taking it from us without asking. That's when it gets more concerning, because that's when it gets harder to fight.