React v0.13.1 Perf

HTML

<script src="http://react.zpao.com/builds/master/latest/JSXTransformer.js"></script>
<script src="https://fb.me/react-with-addons-0.13.1.js"></script>
<script src="http://facebook.github.io/react/js/jsfiddle-integration.js"></script>

JavaScript 1.7

var items = _.chain(_.range(100)).map(function(i) {
  return { id: i, name: "item" + i };
});

class App extends React.Component {
  constructor(props) {
    super(props);
    this.state = {items: [] };
  }
  componentDidMount() {
    React.addons.Perf.start();
    this.setState({ items: items }, function() {
      React.addons.Perf.stop();
      React.addons.Perf.printInclusive();
    });
  }
  render() {
    return (
      <div>
        <List items={this.state.items} />
      </div>
    );
  }
};

class List extends React.Component {
  render() {
    var items = this.props.items.map(function(item) {
      return <div><span>id:{item.id} </span><Item key={item.id} item={item} /></div>;
    });
    return <div>{items}</div>;
  }
};

class Item extends React.Component {
  render() {
    return <span>name:{this.props.item.name}</span>;
  }
};

React.render(<App />, document.body);