T5 Custom Log-out URL Create a custom log-out URL in WordPress.

t5-custom-logout-url.php

<?php
/**
 * Plugin Name: T5 Custom Log-out URL
 * Description: Create a custom log-out URL.
 * Plugin URI:  http://wordpress.stackexchange.com/questions/76161/masking-logout-url
 * Version:     2012.12.14
 * Author:      Thomas Scholz
 * Author URI:  http://toscho.de
 * Licence:     MIT
 * License URI: http://opensource.org/licenses/MIT
 */

add_filter( 'logout_url', 't5_custom_logout_url', 10, 2 );
add_action( 'wp_loaded', 't5_custom_logout_action' );

/**
 * Replace default log-out URL.
 *
 * @wp-hook logout_url
 * @param   string $logout_url
 * @param   string $redirect
 * @return  string
 */
function t5_custom_logout_url( $logout_url, $redirect )
{
  $url = add_query_arg( 'logout', 1, home_url( '/' ) );

	if ( ! empty ( $redirect ) )
		$url = add_query_arg( 'redirect', $redirect, $url );

	return $url;
}

/**
 * Log the user out.
 *
 * @wp-hook wp_loaded
 * @return  void
 */
function t5_custom_logout_action()
{
	if ( ! isset ( $_GET['logout'] ) )
		return;

	wp_logout();

	$loc = isset ( $_GET['redirect'] ) ? $_GET['redirect'] : home_url( '/' );
	wp_redirect( $loc );
	exit;
}