shouldComponentUpdate

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/babel-core/5.8.24/browser.js"></script>
<script src="https://fb.me/react-with-addons-0.14.6.js"></script>
<script src="https://fb.me/react-dom-0.14.6.js"></script>
<script src="https://facebook.github.io/react/js/jsfiddle-integration-babel.js"></script>

<div id="container">
    <!-- This element's contents will be replaced with your component. -->
</div>

Babel + JSX

var Input = React.createClass({
	getInitialState: function() {
  	return {text: ''}
  },
  updateText: function(e) {
    this.props.updateText(e.target.value);
  },
  render: function() {
   return (
  	<input type='text' onChange={this.updateText} />
    )
  }
})

var Text = React.createClass({
  render: function() {
  	return (
    	<div>{this.props.text}</div>
    )
  }
})

var Form = React.createClass({
	getInitialState: function() {
  	return {text: 'empty'}
  },
  shouldComponentUpdate: function(nextProps, nextState) {
    console.log(this.props)
    console.log(nextProps)
    console.log(this.props === nextProps)
  	return nextState.text === 'anton';
  },
  updateTextForm: function(value) {
  	console.log(value);
  	this.setState({text: value});
  },
  render: function() {
    return <div>
    	<Input updateText={this.updateTextForm}/>
      <Text text={this.state.text} />
    </div>;
  }
});

ReactDOM.render(
  <Form />,
  document.getElementById('container')
);