I have created an extension that you basically add a link to a youtube video and it will add the video to play in your post. SO has an example here is a video of my Paintball gun. As of right now to use it.  Hit the HTML button in the menu above and past the url in there and make sure there is a space before and after the url then hit update.  As of right now it only does one video per post. Enjoy.

http://youtube.com/watch?v=C8DOY1FfIqU
 

YouTube.cs (1.60 kb) (Updated :on 11-05-07)

Update 1- code to allow more characters before and after the url. 

Just add to your extensions folder in App_Data folder. 

 
Edit: To use this all you have to do is add the url to your page.  That is it. No special codes or anything JUST the url in your post.