No one likes auto-playing video, but auto-playing previews can be helpful in certain cases. Google recently rolled out video previews on the YouTube desktop site, allowing people to hover over a video to see a glimpse of the contents. Now the company is rolling out video previews on its mobile Search.
Google Search already shows a carousel of related videos on some searches, especially ones with large amounts of video results (like tutorials, reviews, etc).
Google rolling out auto-playing video previews in Search was written by the awesome team at Android Police.