for (var s in categories) {
                    title = categories[s]['name'];
                    //window.alert(title); // returns category name, EG Business or Residence
                    if (!isArray($.bgmp.markers[title])){
                        window.alert('$.bgmp.markers['+title+']not Array, creating it');
                        $.bgmp.markers[title] = [];
                    }
                    $.bgmp.markers[title].push(marker); //should push the marker to the bgmp.markers['Business'] array, but fails.
                }
                $.bgmp.markers.push( marker );