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Why would Google confess to the many problems it has had selling ads? The problems, Google ad-sales exec Tim Armstrong admitted to the Wall Street Journal, extended far beyond YouTube, where Google's bureaucracy compounded advertisers' hesitation to place commercials next to the site's free-for-all video content. Armstrong didn't point fingers, but he didn't have to: Everyone in the Valley knows that Sheryl Sandberg, the high-ranking Google executive who recently defected to Facebook, oversaw Google's automated online-advertising systems.

That's precisely why Facebook hired her as COO — to address similar problems, as Facebook's advertisers have grown more and more noisy in their complaints about the site's broken billing systems. How cleverly devious of Armstrong: He gets to puff his chest out and claim he's solving Google's problems, while quietly casting the blame on an internal rival who departed for the competition.