Code

            jQuery(window).load(function() {

				var vimeoPlayers = jQuery('.flexslider').find('iframe'), player;

				for (var i = 0, length = vimeoPlayers.length; i < length; i++) {
						player = vimeoPlayers[i];
						$f(player).addEvent('ready', ready);
				}

				function addEvent(element, eventName, callback) {
					if (element.addEventListener) {
						element.addEventListener(eventName, callback, false)
					} else {
						element.attachEvent(eventName, callback, false);
					}
				}

				function ready(player_id) {
					var froogaloop = $f(player_id);
					froogaloop.addEvent('play', function(data) {
						jQuery('.flexslider').flexslider("pause");
					});
					froogaloop.addEvent('pause', function(data) {
						jQuery('.flexslider').flexslider("play");
					});
				}

				jQuery(".flexslider")
				.fitVids()
				.flexslider({
					animation: "slide",
					animationLoop: false,
					smoothHeight: true,
					useCSS: false,
					before: function(slider){
						if (slider.slides.eq(slider.currentSlide).find('iframe').length !== 0)
						      $f( slider.slides.eq(slider.currentSlide).find('iframe').attr('id') ).api('pause');
					}
				});

			});

          
            <!-- Place somewhere in the <body> of your page -->
            <div class="flexslider">
              <ul class="slides">
                <li>
                  <iframe id="player_1" src="http://player.vimeo.com/video/39683393?api=1&player_id=player_1" width="500" height="281" frameborder="0" webkitAllowFullScreen mozallowfullscreen allowFullScreen></iframe>
                </li>
                <li>
	  	    		<iframe id="player_2" src="http://player.vimeo.com/video/27243869?api=1&player_id=player_2" width="500" height="281" frameborder="0" webkitAllowFullScreen mozallowfullscreen allowFullScreen></iframe>
  	    		</li>
  	    		<li>
	  	    		<iframe id="player_3" src="http://player.vimeo.com/video/27244727?api=1&player_id=player_3" width="500" height="281" frameborder="0" webkitAllowFullScreen mozallowfullscreen allowFullScreen></iframe>
  	    		</li>
  	    		<li>
	  	    		<iframe id="player_4" src="http://player.vimeo.com/video/27246366?api=1&player_id=player_4" width="500" height="281" frameborder="0" webkitAllowFullScreen mozallowfullscreen allowFullScreen></iframe>
  	    		</li>
  	    	<ul>
            </div>
          

I'm Juanfra Aldasoro founder of Nice Themes. I tweet and write about WordPress.

You should follow me on twitter here.

This page is based on Flexslider's demo.