This script will search /var/www (changeable in a variable) for any wordpress installs and make sure its upgraded to the latest version.
It will run a backup to /root/wp_upgrade/ of all files and database before doing anything with the site in case of major catastrophe (make sure you have spare disk space if your sites have a lot of uploaded files).
It pays to check each site after the upgrade to make sure plugins all worked (and upgrade plugins before the upgrade works also!), and also for some reason the DB updagrade curl does not work so go to the admin end and click the 'upgrade database' link.
Let me know if you have any bugs at all, or any problems.
Here’s your script to upgrade them all.
wget http://b.ri.mu/files/wordpress-upgrade-3.1.1.sh bash wordpress-upgrade-3.1.1.sh