I just installed a modification to SMF that will allow you to imbed a YouTube video into your post.
Example:
To imbed a YouTube video, simply click the

button. You'll then need to enter the YouTube video ID. In the link below, you can see the video ID in
BOLD.http://www.youtube.com/watch?v=3hK7oLlxl_0So as an example, the imbed code looks like this:
[youtube=425,350]3hK7oLlxl_0[/youtube]