There is a reason why the news paper industry moved in the direction that they did. Or do you think they were forced to move this way? Measurement on the web can be more precise and allows to understand the impact of revenue, it's also vastly more distributed than magazines and TV channels of which there's only thousands or so for each while there are literally millions of websites. There's too much noise and fraud on the web to be able to make marketing decisions with little tracking. The W3C is working with Google on establishing what it would take to accomplish this stuff without sharing data, this isn't the approach apple took with its platform in plain disregard for all the apps that run on it, but than again at this point this shouldn't surprise anyone.