Angular: Empty Fiddle

http://angularjs.org/

HTML

<script src="http://code.angularjs.org/angular-1.0.1.js"></script>
<div ng-controller="MyCtrl">
    <div ng-repeat="data in flattenedResults">
        <div class="time"> <span><b>{{data.created_at | badDateToISO | date:'MMM-d-yy'}}</b></span>
    <div> 

     <u ng-show="data.story.length>0">Stories</u>
       <div ng-repeat="story in data.story">
             {{story.title}}{{story.created_at}}
       </div>

     <u ng-show="data.article.length>0">Articles</u>
       <div ng-repeat="article in data.article">
             {{article.title}}
       </div>
    
  </div>
</div>

JavaScript

var myApp = angular.module('myApp', []);
myApp.filter('badDateToISO', function () {
    return function (badTime) {
        var goodTime = badTime.replace(/(.+) (.+)/, "$1T$2Z");
        return goodTime;
    };
});
myApp.controller('MyCtrl', function ($scope) {
    $scope.flattenedResults = [];
    $scope.comments = [{
        "_id": "535e912cc6b93c7b30479454",
            "created_at": "2014-04-28 23:04:36",
            "post_id": "535e912cc6b93c7b30479453",
            "type": "story",
            "story": [{
            "_id": "535e912cc6b93c7b30479454",
                "title": "test story 1",
                "content": "this is my story... 2",
                "created_at": "2014-04-30 22:04:36"
        }],
            "article": "[]"
    }, {
        "_id": "535e912cc6b93c7b30479454",
            "created_at": "2014-04-28 23:04:36",
            "post_id": "535e912cc6b93c7b30479453",
            "type": "article",
            "article": [{
            "_id": "535e912cc6b93c7b30479454",
                "title": "test article 33",
                "content": "this is my article... 33",
                "created_at": "2014-04-30 22:04:36"
        }],
            "story": "[]"
    }, {
        "_id": "535e912cc6b93c7b30479454",
            "created_at": "2014-04-25 23:04:36",
            "post_id": "535e912cc6b93c7b30479453",
            "type": "article",
            "article": [{
            "_id": "535e912cc6b93c7b30479454",
                "title": "test article 1",
                "content": "this is my article... 1",
                "created_at": "2014-04-30 22:04:36"
        }],
            "story": "[]"
    }, {
        "_id": "535e912cc6b93c7b30479454",
            "created_at": "2014-04-28 23:04:36",
            "post_id": "535e912cc6b93c7b30479453",
            "type": "story",
            "story": [{
            "_id": "535e912cc6b93c7b30479454",
                "title": "test story 2",
                "content": "this is my story... 2",
               ...