Google unveiled a simplified and streamlined video page for best possible watching experience to you. To check out this new look all you have to do is opt-in. Click on this link to try it out (anyone can opt-in, but for now page elements are only in English). To revert back to the old video page, use the opt-out link at the top of the new video page or opt out here. Here’s a quick list: Streamlined look and functionality, New "next up" video list, Description and stats areas united, Cleaned up actions bar, Simplified binary ratings, New player sizing and video quality controls, Search results within the page, Temporary absence of right-hand "more from..." videos, Channel banner placement change, New "see more videos" pane.
More info: YouTube Biz blog