Darren Herman is the Founder and President of Varick Media Management, an audience and media buying platform, and a unit of MDC Partners.

DH: We (at VMM) are excited about the promise of the next version of exchanges. A lot of talk has been around real-time bidding and Google should deliver on this. The impact for our clients and the industry is tremendous, as real-time bidding allows intelligent marketers to purchase impression level inventory.

The challenge will be for "real-time bidding" to scale beyond Google as not everyone buys their inventory in one place. After all, PPC advertising is click level bidding and that's 67% Googled and 33% split between Yahoo, MSN and the rest of the industry.

An additional challenge will be for agencies to adopt this new way of buying. They have choices: build out the capability under their own roof, or use outsourced services/platform group. Understanding impression level data and real-time bidding is very quantitative and agencies will soon realize that they have to make very specialized hires. Not sure traditional agency business models can afford a mass of these types of hires.

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