Marker plugin from Datamap

HTML

<script src="http://d3js.org/d3.v3.min.js"></script>
<script src="http://d3js.org/topojson.v1.min.js"></script>
<!-- I recommend you host this file on your own, since this will change without warning -->
<script src="http://datamaps.github.io/scripts/datamaps.world.min.js?v=1"></script>
 <h2>Datamaps Playground</h2>

<p><a href="http://datamaps.github.io/">DataMaps Project Homepage</a>
</p>
<div id="container1" style="position: relative; width: 80%; height: 400px;"></div>

JavaScript

//basic map config with custom fills, mercator projection
    var map = new Datamap({
        scope: 'usa',
        element: document.getElementById('container1'),
        projection: 'mercator',
        geographyConfig: {
            popupOnHover: false
        },
        fills: {
            defaultFill: '#f0af0a',
            lt50: 'rgba(0,244,244,0.9)',
            gt50: 'red'
        },

        data: {
            USA: {
                fillKey: 'lt50'
            },
            RUS: {
                fillKey: 'lt50'
            },
            CAN: {
                fillKey: 'lt50'
            },
            BRA: {
                fillKey: 'gt50'
            },
            ARG: {
                fillKey: 'gt50'
            },
            COL: {
                fillKey: 'gt50'
            },
            AUS: {
                fillKey: 'gt50'
            },
            ZAF: {
                fillKey: 'gt50'
            },
            MAD: {
                fillKey: 'gt50'
            }
        }
    });

map.addPlugin('pins', function(layer, data, options) {
        var self = this,
            fillData = this.options.fills,
            svg = this.svg;

        if (!data || (data && !data.slice)) {
            throw "Datamaps Error - bubbles must be an array";
        }

        var bubbles = layer.selectAll('image.datamaps-pins').data(data, JSON.stringify);

        bubbles.enter()
            .append('image')
            .attr('class', 'datamaps-pin')
            .attr('xlink:href', 'http://a.tiles.mapbox.com/v3/marker/[email protected]')
            .attr('height', 40)
            .attr('width', 40)
            .attr('x', function(datum) {
            console.log('hey')
            var latLng;
            if (datumHasCoords(datum)) {
                latLng = self.latLngToXY(datum.latitude, datum.longitude);
            } else if (datum.centered) {
                latLng = self.path.centroid(svg.select('path.' + datum.centered).data()[0]);
            }
 ...