html-select-hide-afterselect.html

//http://jsfiddle.net/LXp4h/

<script>
  select option {
	color: black;
}
select option:first-child {
	color: grey;
}
select.empty {
	color: red;
}
/* Hidden placeholder */
select option[disabled]:first-child {
	display: none;
}
  
</script>


Re-selectable placeholder<br />
<select>
    <option value="" selected>Please select</option>
    <option value="1">Item 1</option>
    <option value="2">Item 2</option>
    <option value="3">Item 3</option>
</select><br />
Hidden placeholder<br />
<select class="empty">
    <option value="" selected disabled>Please select</option>
    <option value="1">Item 1</option>
    <option value="2">Item 2</option>
    <option value="3">Item 3</option>
</select>