I recently figured out how to post youtube clip to play directly on the post.
1. Find the cool vid to post.
2. Look up at the top of your browser or the link to the site.
3. Copy the link after "v=" before "&" like in the pic example below.
4. type in youtube tag. (like in the pic example below)
5. paste the vid link you had copied between the youtube tag.
Enjoy.
-Mike