&auto.play=1
add that to the end of the url without the period
the determines the width and height of the video, x being width, y being height (i think?)
omitting the =x,y gives you the default embed size
so, example
Code:
[flash]http://www.youtube.com/watch?v=rwhl-LxS4Go
if we use that, we get
<object type='application/x-shockwave-flash' width="250" height="250" data='http://www.youtube.com/v/rwhl-LxS4Go'>
<param name='AllowScriptAccess' value='never' />
<param name='wmode' value='transparent' />
<param name='movie' value='http://www.youtube.com/v/rwhl-LxS4Go' /><param name='play' value='true' />
<param name='loop' value='true' /><param name='quality' value='high' /></object>
if we put in different x and y values...
Code:
http://www.youtube.com/watch?v=rwhl-LxS4Go
we get...
http://www.youtube.com/v/rwhl-LxS4Go
you're going to want to keep a square or rectangular shape going on, though, becausee if you use something like 40,300...
http://www.youtube.com/v/rwhl-LxS4Go
the video looks weird.
if we added &auto.play=1 at the end of either of those videos (without the period between "auto" and "play"), the video we added it to would begin playing upon loading
hope that helps