AngularJS - Selects and ng-options

HTML

<script src="http://code.angularjs.org/1.1.4/angular.js"></script>
<link rel="stylesheet" href="//netdna.bootstrapcdn.com/twitter-bootstrap/2.3.1/css/bootstrap-combined.min.css">
<div ng-app="myapp">
  <fieldset ng-controller="FirstCtrl">
    <select ng-options="key as value for (key , value) in cities " ng-model="selectedCity">
    </select>
    {{ selectedCity }}
  </fieldset>
</div>

JavaScript

var myapp = angular.module('myapp', []);
myapp.controller('FirstCtrl', function($scope) {
$scope.selectedCity='firstCity';
  $scope.cities = {
    firstCity: "NY",
    secondCity: "LA",
    thirdCity: "OT"
  };
});