As a theoretical solution to what you are saying, you could implement this in aggregate -- the ISP accepts a flat "content" payment from all its subscribers, su

As a theoretical solution to what you are saying, you could implement this in aggregate -- the ISP accepts a flat "content" payment from all its subscribers, sums the time spent on each site from each user, and then pays out micropayments to each content provider as a percentage of the total content payments received from all subscribers. Sort of analogous to how the Tor network prevents deanonymization. You could even implement it as an open-source browser extension in the same fashion as Tor. Ultimately however, this solution has two major flaws that I can think of up front -- first, it is too susceptible to botting, and second, it relies on a steadfastly privacy conscious central party (the ISP in this example) that never accidentally hires an Eric Schmidt-type who gives in to the monetary value of data. Having just read Tim Wu's "The Attention Merchants" I don't have a lot of hope for that.