Are vertical networks still relevant in the age of audience targeting? Adify CEO Russ Fradin rejects comparison of horizontal and vertical networks. He argues vertical networks aren't offshoots of
horizontal ad networks but more the evolution of Web portals, explaining why CPMs are more like those on portals than traditional ad networks. Travel Ad Network's Brian Silver says he's been using the
portal analogy for the last two years to explain the importance of context to target advertising, especially for going after the in-market travel audience
