Google Analytics falls into the same category. You're not paying currency to use the service; you're paying with your metrics. When you think about it in terms of scale, this is way worse. Google is great at taking this data and using it to generate revenue in a number of other ways. Any smart advertiser who uses Google Adwords to buy traffic knows to stay away from Google Analytics. Why would you let the company you're buying traffic from know how that traffic behaves?
The DNS project takes this a step further by giving Google a world of new data. Now you don't have to use Google or be on a site with Google Analytics for Google to know where you're going.
Seems harmless, but I bet they can't wait for this to be adopted by the masses.
With all that being said, 8.8.8.8 is a damn cool IP address and I'm sure my Google-powered Droid already uses it. /rant