We have added a bbcode that allows you to insert youtube videos.
You will find the button on the top right of your reply box. To adda youtube video to your post simply click that and insert the video url from the address box of your browser.
As an example I'm using Thorrshamri's video from here: viewtopic.php?f=47&t=11895
Like such:
[youtube]http://www.youtube.com/watch?v=L8xaULa5Fu0[/youtube]
The url originally read: http://fr.youtube.com/watch?v=L8xaULa5Fu0
In order for the embedded video to work simply replace the fr. (or uk., etc) with www.
Enjoy