YouTube has a new "Lights Off" Feature similar to Hulu's "Lower Lights" and MegaVideo's "Cinema" features respectively.

Here is the button which activates it. It's located just above the video in the right.
http://img233.imageshack.us/img233/453/picture10dd0.png

Here is the page before the feature has been activated
http://img178.imageshack.us/img178/9813/picture12ys1.png

Here is the Page after
http://img212.imageshack.us/img212/8186/picture11nr5.png

This is MegaVideo's similar feature
http://img201.imageshack.us/img201/5331/picture15me2.png

see:http://googlesystem.blogspot.com/2008/10/youtube-theather-view.html
It was introduced with the 16:9 Player. It only appears only on Full Length videos

Aww...

Still, the screenshot here is far different to the one in that post.

http://2.bp.blogspot.com/_ZaGO7GjCqAI/SOqEpexck4I/AAAAAAAAL9U/nRpcwiotQ3o/s640/youtube-theater-view-2.png
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