Youtube recently announced they would be changing the size and aspect ratio of the standard video player on their site.

We’re expanding the width of the page to 960 pixels to better reflect the quality of the videos you create and the screens that you use to watch them. This new, wider player is in a widescreen aspect ratio which we hope will provide you with a cleaner, more powerful viewing experience. And don’t worry, your 4:3 aspect ratio videos will play just fine in this new player.

Videos uploaded in the old 4:3 aspect ratio will appear to be “inset” in More >