Twitch has been lagging well behind most every other large streaming and video site when it comes to implementing an HTML5 video player. They expected the HTML5 player to have been released earlier this year, but they seem to have had more important things to attend to.

Fortunately, HTML5 streaming and video playback are finally starting to come this July.

The beta will begin this July, but only for Twitch Turbo subscribers. If the beta goes well, they expect the beta access to expand to more users towards the "end of Summer." What year? No idea, but hopefully they meant Summer 2016.
So why has it taken us so long to get to this point? Our top priority in building an HTML5 video player has been to make sure you can watch the same streams you love in a noticeably smoother package. When faced with the decision of releasing a product that did not meet our quality standards or spending more time to fine-tune your viewing experience, we made the hard choice to delay our release past our second quarter deadline. After months of hard work, we finally have just a few finishing touches to wrap up before we start our beta test.

The focus of this beta will be on identifying breaking points and areas for improvement. There are still several systems, including ad support, that are not quite ready for a full release, so we are starting the beta with users who do not see ads site-wide. Though some partners have enabled Ad-Free Viewing for their subscribers, subscribers may watch many channels on Twitch, making it tricky to gather consistent data from those users. We also need lots of feedback and lots of minutes watched, which made Turbo subscribers the perfect group to kick off our HTML5 test, since they watch video at significantly higher rates than any other users on Twitch.

YouTube has had HTML5 playback enabled by default for about a year and a half now. Twitch competitor, Hitbox, has had full HTML5 implementation since March of this year.