In conclusion, the online advertising experiment in which so many of us have engaged is really only ten years or so old. Those who say that it's "mature" are not only mistaken, but they drastically underestimate what a true break the web is from the offline media that came before. We've had a few hundred years to learn to monetize print, over 75 years to monetize TV, and, most importantly, millennia to build business models based on scarcity. In contrast, our collective effort to monetize post-scarcity digital media have only just begun. - George Kelly