AngularJS: ng:model-instant form

HTML

<script src="https://raw.github.com/msgilligan/msgilligan.github.com/master/samples/angular-bootstrap/js/angular-0.10.7-b9bcc0f6.js"></script>
<div ng:controller="NavBarCtrl">
  <form name="testSearchForm" ng:submit="testSearch(testSearchInput)">
    <input type="text" name="testSearchInput" ng:model="testSearchInput" ng:model-instant placeholder="Test me">
  </form>
</div>

JavaScript

function NavBarCtrl($scope) {
    $scope.testSearch = function(input) {
        alert(input);
    };
}