// ==UserScript==
// @name           YouTube Auto-play Preventer
// @description    Stops the YouTube player from playing automatically
// @include        http://www.youtube.com/watch*
// @include        http://youtube.com/watch*
// @author         Protector one
// @date           22-9-2009
// @version        2.0
// ==/UserScript==

var launch = 1;

function stateChanged(event){
  if(event == 1 && launch){
    setTimeout(stopIt,10);
    if (launch++ == 1)
      setTimeout(finalCheck,5000);
  }
}
function stopIt(){
  var ob = document.getElementsByTagName('object')[0];
  ob.pauseVideo();
  ob.seekTo(0,0);
}
function finalCheck(){
  launch = 0;
  if (document.getElementsByTagName('object')[0].getPlayerState() != 0)
    stopIt();
}

document.getElementsByTagName('object')[0].addEventListener('onStateChange','stateChanged');