The YouTube method has been changed, as of today, so the syntax is the same as embedding Vimeo videos.
ie; All you need to do is cut & paste the video id only between the relevant [ YouTube ] or [ Vimeo ] tags.
Beware of other junk in a YouTube URL, often there is "&feature= blah blah - you just need the video id here
Please keep in mind that some users do not have access to high-speed internet, so it may be undesirable to embed any more than one or two videos on the same page.