[devote]

<input id="input1" type="text" />
<input id="input2" type="text" />
<script type="text/javascript" src="http://code.jquery.com/jquery.min.js"></script>
<script type="text/javascript">
    $("#input1").keyup( function( e ) {
        $("#input2").val( this.value );
    });
</script>