Videogame play is becoming a spectator sport.

"It is the next evolution in gaming," said Matthew DiPietro of TwitchTV, an online platform that enables people to stream play live online.

"Videogames are becoming spectator content in their own right."

More than 17 million people monthly watch videogame play streamed using TwitchTV, which boasts partners such as the Electronic Sports League, Major League Gaming and IGN Pro League.

"Competitive game play has been around a long time, and on an Internet video platform it fits just right," DiPietro said as the company showed off innovations at the E3 videogame extravaganza that ends Thursday in Los Angeles.

TwitchTV enticed videogame makers with technology that could be embedded in titles to let people easily and instantly stream play online.

TwitchTV was created by the founders of live video streaming platform Justin.tv -- Justin Khan and Emmett Shear.

Shear, a devotee of military strategy videogame "StarCraft," noticed that lots of people were using Justin.tv as a stage for live play, according to DiPietro.

"We started taking it seriously, building features specifically for gaming," DiPietro said of the five-year-old San Francisco-based Internet firm.

TwitchTV launched a year ago and some months later made a partnership with television titan CBS to get money-making video and display ads to weave in during breaks in live game play.

"A lot of gamers are able to literally quit their jobs and make livings from streaming on Twitch," DiPietro told AFP.

"If you are between levels or go use the restroom or grab a Red Bull you can just push a button and run an ad."

Twitch splits ad revenue with those behind game play, but would not reveal details of how the money is divided.

Twitch "broadcasters" range from professional gaming leagues to individual players.

"Players have become celebrity personalities in their own right," DiPietro said.

Watching or streaming game play is free. TwitchTV has dabbled with subscription or pay-per-view models for some of its big league partners.

Games played run the gamut, but among the more popular were "League of Legends," "Minecraft," and freshly released "Diablo III."

There is even a massive fan base for "speed running" in which players blast through videogames as quickly and flawlessly as possible.

Of course, viewers tune into watch play of blockbuster shooter games such as "Call of Duty" and "Halo."

"Game play by people talented at these games is so astoundingly compelling that you want to watch it live," DiPietro said.

Twitch bills itself as the world's leading videogame broadcasting network.