Zoom to Double Click

Instead of zooming around double-clicked points, zoom to them
<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8 />
<title>Zoom to Double Click</title>
  <meta name='viewport' content='width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no' />
  <script src='//api.tiles.mapbox.com/mapbox.js/v1.4.0/mapbox.js'></script>
  <link href='//api.tiles.mapbox.com/mapbox.js/v1.4.0/mapbox.css' rel='stylesheet' />
  <!--[if lte IE 8]>
    <link href='//api.tiles.mapbox.com/mapbox.js/v1.4.0/mapbox.ie.css' rel='stylesheet'>
  <![endif]-->
  <style>
    body { margin:0; padding:0; }
    #map { position:absolute; top:0; bottom:0; width:100%; }
  </style>
</head>
<body>
<div id='map'></div>
<script type='text/javascript'>
var map = L.mapbox.map('map', 'examples.map-9ijuk24y', {
    // disable default double-click behavior
    doubleClickZoom: false
})
.setView([40, -74.50], 9)
// zoom exactly to each double-clicked point
.on('dblclick', function(e) {
    map.setView(e.latlng, map.getZoom() + 1);
});
</script>
The code and documentation to mapbox.js is hosted on GitHub where you can contribute changes and improvements.