YouTube’s ongoing effort to keep visitors on its pages for longer took a new twist today, when the video portal said it will start ranking videos by how long people watch them. The move makes it more difficult to game the system by choosing a provocative thumbnail image for your video in an effort to drive clicks. Instead, creators will be rewarded for actually getting viewers to watch the whole video. It follows a similar change the Google-owned company made to its suggested videos feature earlier this year. “These changes better surface the videos that viewers actually watch, over those that they click on and then abandon,” the company said … Continue reading Casey Newton