We try to provide information about how Facebook works, how information is shared in a number of different ways, in addition to the data use policy. Obviously we provide the data use policy to every user of Facebook before they can access our site. We require them to accept it, and we hope they do read it.
We also provide information about how information is shared in a number of different ways, including in our interface. For example, we have the inline privacy controls, which, if you have used our site, you're familiar with: when you're posting, you get to make a judgment about who will see that information.
We think there are a number of different ways that we provide information to people. We also have a help centre where you can search for information if you want to know about how we do a particular thing and hope that makes the information accessible. We do try to provide a readable data use policy.