Drupal: TinyMCE Youtube Plugin
You can not use
YouTube’s “embedable” code snippet in a WYSIWYG Javascript editor like
TinyMCE. That can get very uncomfortable, leading to frequent need to
switch back-and-forth between the HTML view and WYSIWYG view. Not
user-friendly at all. Fortunately, TinyMCE does have a “plugin” that
supports Youtube.
Download: file youtube_xhtml_workaround.zip from the
YouTube
Button
Issue ticket on SourceForge. Direct
Link
Follow the instructions at:
http://drupal.org/node/154877#comment-253803