When I was in the seventh grade, I had a crush on an eighth grader and documented my secret love on a scrap of paper. Somehow it ended up in the possession of my obnoxious classmate, Myiia, who refused to give it back.

A vice principal got involved when he saw us arguing in the hall. After extracting a lengthy (and embarrassing) explanation from me, he returned my doodles. I confronted an unrepentant Myiia about it later, and she gave me some trenchant advice about privacy: “Never write anything down,” she sniffed, “that you don’t want the whole world to know.”

As much as I hated to admit it, those were wise words when they were spoken in the 1980s – a simpler time, to be sure. In the Facebook era, practically everything we do with a computer gets written to a hard drive immediately – not only the documents we type, but also the sites we visit, the conversations we have and the friends we make.

That reality has rendered Myiia’s advice obsolete. Since pretty much everything we do gets recorded somewhere, what does privacy mean anymore?

Privacy used to be more about seclusion. We closed the bathroom door to “get a little privacy.” We put locks on our diaries to keep their contents private. In today’s digital world, however, it increasingly means something different: control. For an Internet service, that means giving users the power to decide who sees their data and when. It means giving them the power to take it elsewhere. It means giving them the power to delete it.

Which brings me to Facebook. People are giving CEO Mark Zuckerberg a lot of flack about Facebook’s privacy controls, and some of that criticism is warranted. Yes, he took a site that was originally for college students and opened it to the rest of the world, a move that some felt betrayed their expectation of privacy. He rolled out (and then shut down) Beacon, an intrusive service that broadcast user online activities back to their friends. The company has deleted or suspended Facebook accounts for reasons that are sometimes unclear. Recently Facebook changed its default settings in a way that made many user status updates and comments public, effectively taking what some felt was a private message board and turning it into a public blog.

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And he keeps pushing us to share more and more. Earlier this week, he explained why. One, he believes the world becomes a better place when we communicate more meaningfully with others. Two, the more openly people share, the more quickly Facebook grows its user base.

He’s not doing it to make more money from targeted advertising, as he explained during Wednesday’s privacy press conference. In his words:

“There’s this idea going around that somehow if people share information more openly, that we can use it better for ad targeting. And it’s actually the opposite.

“First of all, advertisers don’t get any information from the system. There are bugs that we sometimes have, and that sucks, and we need to do a better job of making sure we don’t have them. But the principles of the system are, we don’t give any information to advertisers. We target all the ads ourselves. Advertisers come to us and say here’s what I want to advertise to this set of people. We take the ad and we show it to the person who we think is interested in it.

“Because of that and the way the system works, it doesn’t matter who you’re sharing information with. You could share it with your friends, you could share it openly with everyone, and it doesn’t affect the ads at all.

“One interesting way it does affect the ads is, there’s this concept of data portability, which is something that we are trying to enable through Facebook Connect and Platform, which is that people own their information. That means not only should they have control over how it works on Facebook, but they should be able to take it to other services too, if they want. And once they bring it to another service, then that service can also use it to compete with us and target ads.

“So by doing what we’re doing to push data portability forward and make these platforms more interoperable, we’re actually helping other people compete with us in advertising.”

Even if you detest Facebook’s privacy approach, from a technical perspective, Zuckerberg’s explanation holds up. He’s not doing it for the money. It’s for the growth.

Still, here’s why I tend to give Zuckerberg the benefit of the doubt on this one. Though he makes mistakes, he also seems to listen to his customers. (Note the new privacy controls Facebook released this week.) And this stuff isn’t easy: As the foremost pioneer in social networking, Zuckerberg and his team are creating arenas of communication that never existed before, so they have to make the rules up as they go. He’s bound to get some things wrong. And as a daily Facebook user, I really do think he’s given the world a wonderful tool that has changed communication forever. I now have a window into the lives of literally hundreds of long-lost friends. And I can stay connected to them without having to, you know, write them. Or talk.

Besides having given us this gift of passive connection, Zuckerberg has also gotten one key thing right about the Facebook system: He actually offers privacy controls.

The controls go way beyond the ability to take charge of what others learn about you on Facebook. You can also see what Facebook knows about you. On Facebook, you can plainly see much of the data the site has on you, because it’s posted to your wall. You can see your friend list, marital status, previous jobs, interests, likes – all the things Facebook uses to determine who you are. You can see the links you’ve posted, and the ones your friends have posted.

How many other companies do that? Where are Google’s (GOOG) privacy controls? Or Visa’s? (V) Or Apple’s (AAPL)? Or Amazon’s (AMZN)? All of those businesses collect a frightening amount of data about their customers, yet there’s nowhere we can go to see exactly what they know. They purport to allow us to control who sees our data, but I can’t find where any of them offers a privacy control page that makes this clear.

Based on that, I would argue that Zuckerberg is doing a decent job on privacy. Do I trust him completely? Well, no. The default privacy settings Facebook recommends are way too open for my taste, so I’ve taken the time to categorize my friends and set multiple levels of access. But I appreciate that he’s given us the power to make those tweaks.

Of course, I’m a little paranoid. I can thank a seventh grader named Myiia for that.