For IE9, 8, 7, 6 check user's version of Flash Player. If it's less than 11.5, use static image for background and show div prompting them to upgrade.

gistfile1.js

  var bgImageInit = function(mobile) {
    var bg_image = "#{image_path('application/mobile-splash-bg.jpg')}";
    $('#main-container').css('background', 'url(' + bg_image + ') right top no-repeat');
    if (mobile == true) {
      $('#main-container').css('background-size', '70%');
    }
  }

  var mobileInit = function() {
    var BV = new $.BigVideo({forceAutoplay:is_touch});
    BV.init();
    BV.show("#{image_path('application/temp-background.jpg')}");  
  }

  var bigVideoInit = function() {
    var BV = new $.BigVideo({useFlashForFirefox:false});
    BV.init();
    BV.show("#{asset_path('raved_landing_FINAL_white.mp4')}", { altSource: "#{asset_path('raved_landing_FINAL_white.oggtheora.ogv')}" });
  }

  var is_touch = Modernizr.touch;
  if (is_touch) {
    if ( $(window).width() < 769)  {
      bgImageInit(true); 
    } else {
      mobileInit();
    };
  } else {
    if ($('html').hasClass('check-flash')) {
      _V_.options.techOrder = ["flash", "html5", "links"];
      if (FlashDetect.versionAtLeast(11, 5)) {
        bigVideoInit();
      } else {
        nonBigVideo(false);
        $('#update_player').show();
        $('#update_player a.close').click(function(){
          $(this).parent().hide();
        });
      }
    } else {
      bigVideoInit();
    }
  }