The YouTube video page is getting a makeover. The goal is to improve its user experience.
To do so, the video player has been updated, and it has been changed the way recommendations and information is displayed. Sharing, embedding and rating information has been simplified, too.
The user rating systems has move to a "like or dislike" model, which users can designate by clicking a "heart" or "thumbs down" symbol.
The video player shows the ability to switch between multiple quality levels.
For now, the new design is only available if you opt-in to use.
Here is a link with the new design. And here is the official explanation.