Media: YouTube
http://drupal.org/project/media_youtube
Media and Media: YouTube modules
http://drupal.org/project/media
&
http://drupal.org/project/media_youtube
Drupal 7 video setup using the Media and the Media_Youtube Modules - Clever Logic Video
http://cleverlogic.net/tutorials/drupal-7-video-setup-using-media-and-media-youtube-module