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ENGADGET: Opera buys Skyfire, wants its video and smartphone optimization expertise

"Guys are intimidated to drive the lane because he blocks everything, and shots he doesn't block, he changes, " Adams said.

WSJ: Prediction: This Won't End Well For NYU-Poly

The departure will result in some significant changes because, according to Mr. Karp, Mr. Maloney has put "everything in order" at Tumblr, from paying the bills to wooing investors, hiring staff and steering day-to-day operations.

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