It turns out he's Google's Chief Economist (who knew - Google has a chief economist?). A recent Steven Levy piece in Wired magazine talks about the ways the company uses economic theory (and auction theory in specific) in their Google AdWords program. Here are a couple of snippets:
At the time, most online companies were still selling advertising the way it was done in the days of Mad Men. But Varian saw immediately that Google's ad business was less like buying traditional spots and more like computer dating. "The theory was Google as yenta—matchmaker," he says. He also realized there was another old idea underlying the new approach: A 1983 paper by Harvard economist Herman Leonard described using marketplace mechanisms to assign job candidates to slots in a corporation, or students to dorm rooms. It was called a two-sided matching market. "The mathematical structure of the Google auction," Varian says, "is the same as those two-sided matching markets."Read the whole thing here.Varian tried to understand the process better by applying game theory. "I think I was the first person to do that," he says. After just a few weeks at Google, he went back to Schmidt. "It's amazing!" Varian said. "You've managed to design an auction perfectly."
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AdWords was such a hit that Google went auction-crazy. The company used auctions to place ads on other Web sites (that program was dubbed AdSense). "But the really gutsy move," Varian says, "was using it in the IPO." In 2004, Google used a variation of a Dutch auction for its IPO; Brin and Page loved that the process leveled the playing field between small investors and powerful brokerage houses. And in 2008, the company couldn't resist participating in the FCC's auction to reallocate portions of the radio spectrum.
Google even uses auctions for internal operations, like allocating servers among its various business units. Since moving a product's storage and computation to a new data center is disruptive, engineers often put it off. "I suggested we run an auction similar to what the airlines do when they oversell a flight. They keep offering bigger vouchers until enough customers give up their seats," Varian says. "In our case, we offer more machines in exchange for moving to new servers. One group might do it for 50 new ones, another for 100, and another won't move unless we give them 300. So we give them to the lowest bidder—they get their extra capacity, and we get computation shifted to the new data center."