WP / Custom taxonomies input panels

<?php
add_action( 'init', 'create_theme_taxonomy', 0 );

function create_theme_taxonomy() {
    if (!taxonomy_exists('theme')) {
        register_taxonomy( 'theme', 'post', array( 'hierarchical' => false, 'label' => __('Theme'), 'query_var' => 'theme', 'rewrite' => array( 'slug' => 'theme' ) ) );

        wp_insert_term('Beauty', 'theme');
        wp_insert_term('Dragons', 'theme');
        wp_insert_term('Halloween', 'theme');
    }
}

function add_theme_box() {
    add_meta_box('theme_box_ID', __('Theme'), 'your_styling_function', 'post', 'side', 'core');
}

function add_theme_menus() {

    if ( ! is_admin() )
        return;

    add_action('admin_menu', 'add_theme_box');

   /* Use the save_post action to save new post data */
    add_action('save_post', 'save_taxonomy_data');
}

add_theme_menus();

// This function gets called in edit-form-advanced.php
function your_styling_function($post) {

    echo '<input type="hidden" name="taxonomy_noncename" id="taxonomy_noncename" value="' .
            wp_create_nonce( 'taxonomy_theme' ) . '" />';


    // Get all theme taxonomy terms
    $themes = get_terms('theme', 'hide_empty=0');

?>
<select name='post_theme' id='post_theme'>
    <!-- Display themes as options -->
    <?php
        $names = wp_get_object_terms($post->ID, 'theme');
        ?>
        <option class='theme-option' value=''
        <?php if (!count($names)) echo "selected";?>>None</option>
        <?php
    foreach ($themes as $theme) {
        if (!is_wp_error($names) && !empty($names) && !strcmp($theme->slug, $names[0]->slug))
            echo "<option class='theme-option' value='" . $theme->slug . "' selected>" . $theme->name . "</option>\n";
        else
            echo "<option class='theme-option' value='" . $theme->slug . "'>" . $theme->name . "</option>\n";
    }
   ?>
</select>
<?php
}

remove_meta_box('tagsdiv-theme','post','core');

function save_taxonomy_data($post_id) {
// verify this came from our screen and with proper authorization.

    if ( !wp_verify_nonce( $_POST['taxonomy_noncename'], 'taxonomy_theme' )) {
        return $post_id;
    }

    // verify if this is an auto save routine. If it is our form has not been submitted, so we dont want to do anything
    if ( defined('DOING_AUTOSAVE') && DOING_AUTOSAVE )
        return $post_id;


    // Check permissions
    if ( 'page' == $_POST['post_type'] ) {
        if ( !current_user_can( 'edit_page', $post_id ) )
            return $post_id;
    } else {
        if ( !current_user_can( 'edit_post', $post_id ) )
        return $post_id;
    }

    // OK, we're authenticated: we need to find and save the data
    $post = get_post($post_id);
    if (($post->post_type == 'post') || ($post->post_type == 'page')) {
           // OR $post->post_type != 'revision'
           $theme = $_POST['post_theme'];
       wp_set_object_terms( $post_id, $theme, 'theme' );
        }
    return $theme;

}