I have released the latest version of WordPress plugin updater script on Github
Wiki: https://github.com/droidzone/wordpress_plugin_updater/wiki
Code: https://github.com/droidzone/wordpress_plugin_updater

WordPress plugin updater is a useful perl script that when run on a folder containing your wordpress plugins, checks each plugin for newer versions in the WordPress repository, and updates each plugin to the latest version.

It accepts as argument a single folder or multiple folders of wordpress installations. This saves you the trouble of visiting your dashboard to update plugins, especially if you manage multiple sites, and have hundreds of plugins. Having older versions of plugins is a security hole, and hence this script helps secure your server.

You can easily run the script as a cron job at hourly-daily intervals and thus schedule updating your plugins.