Felix Salmon contends that social network data is better than a paywall:
[N]ewspapers with a cover price tend to have higher ad rates than free sheets, because their readership is more affluent and is also more likely to actually read the paper (and see its ads).But essentially what’s happening here is that advertisers are using willingness to pay for a newspaper as a proxy for all manner of other desirable traits in newspaper readers, just because there’s no other way of really knowing who’s reading what...
[But the] fact is that if I sign in to a free site using my Twitter login, I’m actually more valuable to advertisers than if I paid to enter that site. That’s because the list of people I follow on Twitter says a huge amount about me, and a smart media-buying organization can target ads at me which are much more narrowly focused than if all they knew about me was that I was paying to read the Times.
Drum is melancholy about the death of privacy.