Okay this is an example for the new embed code for youtube videos.
<iframe title="YouTube video player" class="youtube-player" type="text/html" width="560" height="345" src="http://www.youtube.com/embed/8v_4O44sfjM" frameborder="0" allowFullScreen></iframe>
if you want to autoplay it, at the src="http://www.youtube.com/embed/8v_4O44sfjM"
add the ?autoplay=1
parameter
So the code will look like this:
<iframe title="YouTube video player" class="youtube-player" type="text/html" width="560" height="345" src="http://www.youtube.com/embed/8v_4O44sfjM?autoplay=1" frameborder="0" allowFullScreen></iframe>
i tried this on my blog and it works ! Hope this help (: