"Amazon and Twitch optimize for our customers first and are both believers in the future of gaming," Twitch CEO Emmett Shear said in a statement. "Being part of Amazon will let us do even more for our community. We will be able to create tools and services faster than we could have independently. This change will mean great things for our community, and will let us bring Twitch to even more people around the world."
For Amazon, the purchase is the latest in a series of high-profile moves involving video games. In addition to a music, movie and television streaming device, the company's recently launched Fire TV is also being positioned as a gaming system—one that has the backing of Electronic Arts, Ubisoft, Sega and Disney.
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The retailer has also quietly been building its own game-making studio. In February, Amazon acquired Double Helix Games, maker of "Killer Instinct" on the Xbox One and the classic title "Earthworm Jim." At the same time, it has been recruiting top- level talent from around the industry, including Kim Swift, designer of Valve Software's "Portal" and "Far Cry 2" lead Clint Hocking.
"I think we're going to see Amazon's name pop up more and more," John Taylor, managing director at Arcadia Investment told CNBC in June. "They're looking at formats of the future, which are much more open and support a wider variety of business models. These fundamentally create less friction between the game provider, the developer and the user. "
—By Chris Morris, special to CNBC