Custom Meta Box, working but not saving values

Hi Guys,

I’ve been wrestling with this all day and I can’t work out whats going wrong.

I’ve got the custom meta boxes displaying; a text box and a drop down list, but I can’t get them to save their values to the database.

Am I missing something really simple?? Any guidance would be really appreciated.

Here’s my code:

<?php
function at_post_meta (){
	global $post;
	$custom = get_post_custom($post->ID);
	$at_slider_featured = $custom["at_slider_featured"][0];
	$at_other_author = $custom["at_other_author"][0];
	?>
	<p>
	<label>Featured Slider:</label><br/>
	<select name="at_slider_featured">
		<option value="false">False</option>
		<option value="true">True</option>
	</select>
	</p>
	<p>
	<label>Other Author:</label><br/>
	<input size="25" name="at_other_author" value="<?php echo $at_other_author; ?>" />
	</p>
<?php
	}

function add_at_post_box(){
	add_meta_box(
		"at_post_info",
		"Post Details",
		"at_post_meta",
		"post",
		"side",
		"core"
	);
}

function save_at_post_meta(){
	global $post;
	update_post_meta($post->ID, "at_slider_featured", $_POST["at_slider_featured"]);
	update_post_meta($post->ID, "at_other_author", $_POST["at_other_author"]);
}

add_action( 'admin_init', 'add_at_post_box');

add_action('save_post', 'save_at_post_meta');

add_action('publish_post', 'save_at_post_meta');
?>

Thanks so much for any help

Matt