Mark Zuckerberg wants to be your friend. He just made his 550 millionth the other day and probably will not stop even if he reaches a billion. It’s not simply that he desires to give you an occasional poke, maybe even send you an invitation to help him build a barn in Farmville. No, he wants you to be part of his social network, a sprawling virtual empire whose denizens freely divulge more information than Big Brother would ever know what to do with. And why might you ask? For the good of mankind, of course.

Facebook is a strange and mysterious beast. I still remember creating my account as a freshman. At the time, it certainly didn’t seem earth-shattering—just another college rite of passage, a convenient catalog for a burgeoning group of new friends and romantic interests. To be honest, I felt a little embarrassed at first to even admit I was a part of it. Yet, as the semesters dragged on, I found myself frequently signed onto the network. The stream-of-consciousness status updates, last night’s party pictures, the closet voyeurs—people were getting hooked on this thing, and it didn’t take a genius to notice what was happening. Sitting in the back row of any lecture hall, it is not uncommon to see that at least half of the class is logged on and tuned out. How did it get to this? Well, it all comes down to audience. And on Facebook, your audience is your friends.

The Internet was not always like this. In the beginning, anonymity ruled. On the Internet you could be anyone, say anything, and go anywhere without leaving a trace of your identity. The ability to be invisible was a huge draw for many. Yet, the freedom of anonymity invited abuse. Not only did it give free rein to creeps and weirdos, it provided a new battleground for ideological arguments bogged down by pejorative and dogmatism. The internet became a shouting match among strangers in which the person who could type the most words per minute wielded the biggest gun in the room. It was suffocating.

And then came Facebook, a way to re-order the internet according to the perspectives of the people who really matter: your friends. They are your audience, privy to the “factual” information you present about yourself, and always up-to-date on your status. The internet user went from being cloaked in the shallow comfort of anonymity to the gratuitous exposure of hyper-sociability. The information we post, the profile picture we select, all an elaborate ritual to put our best face forward, even if that face is nothing more than a compartmentalized and easily disseminated version of ourselves. Take one trip to the back of the lecture hall and you will see that we are no more capable of pulling ourselves away from our profile than Narcissus was able to look away from his reflection in the pond.

You might be wondering, “To what end?” Is Facebook making our society more open, more transparent? Is it facilitating the freer exchange of information, or is it just another way to keep tabs on the Joneses?

It’s undeniable that Facebook is charting a new geography: it’s the cartographer of our social relations. But that is not all that it is mapping. It is also providing the Cartesian coordinates for targeted marketing, our latitude and longitude in a consumer society. Visit a popular Web page and it will prompt you to “sign in” with Facebook. It has become your internet ID, a fast and easy way for companies to make more money by showing you what you want to see. And why shouldn’t they—you told them what you “like”—and that’s a terrible piece of information for a company to waste.

Mark Zuckerberg wants to be your friend. He’s upgrading the layout, constantly tweaking its features, and securing new partners. Everyone is doing it. Even Goldman Sachs is throwing gas on the fire. The question is, “Will you accept his invitation?”