test.html

<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title></title>
</head>
<body>
<script src="http://fb.me/react-0.12.2.js"></script>
<script src="http://fb.me/JSXTransformer-0.12.2.js"></script>

<script type="text/jsx">
    var TextInput = React.createClass({
        propTypes: {
          value: React.PropTypes.string,
          onChange: React.PropTypes.func
        },
        render: function(){
            return <input type="text" value={this.props.value} onChange={this.props.onChange} />
        }
    });

    var Me = React.createClass({
        getDefaultProps:function(){
          return {
              name: 'benjamin'
          }
        },
        propTypes: {
            name: React.PropTypes.string
        },
        render: function(){
            var name = this.props.name;
            return <span>{name}</span>
        }
    });

    var App = React.createClass({
        getInitialState:function() {
          return {
              name: 'Benjamin'
          }
        },
        updateName: function(e){
            this.setState({name: e.target.value})
        },
       render: function(){
           return (
                           <div>
                               <TextInput value={this.state.name} onChange={this.updateName} />
                               <h1>Hello <Me name={this.state.name} /></h1>
                           </div>
                   )
       }
    });

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