mapbox.js vectors via @bobws

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <html>
  <head>
  <link href='https://api.tiles.mapbox.com/mapbox.js/v1.0.0/mapbox.css' rel='stylesheet' />
  <script src='https://api.tiles.mapbox.com/mapbox.js/v1.0.0/mapbox.js'></script>

// Set base style of vector data
    function style(feature) {
      return {
        weight: 0,
        fillOpacity: 0.5,
        fillColor: '#FFEDA0'
      };
    }

// Set hover colors
    function highlightFeature(e) {
      var layer = e.target;
      layer.setStyle({
        weight: 10,
        opacity: 1,
        color: '#09F',
        dashArray: '3',
        fillOpacity: 0.7,
        fillColor: '#FEB24C'
      });
    }

// A function to reset the colors when a neighborhood is not longer 'hovered'
    function resetHighlight(e) {
      geojson.resetStyle(e.target);
    }

// Tell MapBox.js what functions to call when mousing over and out of a neighborhood
    function onEachFeature(feature, layer) {
      layer.on({
        mouseover: highlightFeature,
        mouseout: resetHighlight
      });
    }

// Add vector data to map
    geojson = L.geoJson(neighborhoods, {
      style: style,
      onEachFeature: onEachFeature
    }).addTo(map);

// Here is where the magic happens: Manipulate the z-index of tile layers,
    // this makes sure our vector data shows up above the background map and
    // under roads and labels.
    var topPane = map._createPane('leaflet-top-pane', map.getPanes().mapPane);
    var topLayer = L.mapbox.tileLayer('landplanner.map-0wnm9063').addTo(map);
    topPane.appendChild(topLayer.getContainer());
    topLayer.setZIndex(7);

</script>
</body>
</html>

Modified http://api.tiles.mapbox.com/mapbox.js/v1.0.0/mapbox.js to a secure url

Updated missing url http://bl.ocks.org/rsudekum/raw/5431771/nycneighborhoods.js to /rsudekum/5431771/example/nycneighborhoods.js

https://api.tiles.mapbox.com/mapbox.js/v1.0.0/mapbox.js

https://bl.ocks.org/rsudekum/raw/5431771/nycneighborhoods.js