With Eben Moglen’s Freedom Boxes in our minds, I will paraphrase Danny O’Brien, who talked about the Web 2.0 privacy paradox in his Living on the Edge talk.
When you want share a private message with just one person (or some other group of people), you first have to give this message to a Faceless Corporation, which will make sure that only their servers and that other person will see this message.
To which I will add: in the meantime they’ll read this message and sell advertising against it to other Faceless Corporations. The architecture of the internet doesn’t need the Faceless Corporation, so people can send private messages to each other.