Sample usage :

If the URL of the youtube video is : http://www.youtube.com/watch?v=2VaL8kgoI8Y

The video ID is : 2VaL8kgoI8Y

And to embed the video in your post, you need to enter the YouTube tags around the video ID:

Code:
[UTUBE]2VaL8kgoI8Y[/UTUBE]

The result will be :


[YOUTUBE]Gw9Q1y9RkUY[/YOUTUBE]