I’m a big fan of having machines help us with the lower level tasks, freeing up time, resources and brain power for more interesting and complex tasks. Julia [the artificial intelligence system that HuffPo owns] takes that a few steps further and helps us with a lot of other aspects of HuffPost in addition to helping weed out abusive members, including identifying intelligent conversations for promotion, and content that is a mismatch for our advertisers. She has allowed us to do a lot more with a lot less.

"We wouldn't put our money where we don't know the numbers, just as you wouldn't invest in a stock," [Starcom's Chris] Bailes said.

"I can go to the Guardian or CNN and get an audience... No one is indispensable."

Executives in Microsoft's new ad business were upset when the designers of Internet Explorer hatched the plan to block tracking activity, say people involved in the debate. At a meeting in the spring of 2008, Brian McAndrews, a Microsoft senior vice president who had been chief executive of aQuantive before Microsoft acquired it, complained to the browser planners. Their privacy plan, he argued, would disrupt the selling of Web ads by Microsoft and other companies, these people say.