To avoid any problems with your filesystems always shutdown your debian box the neat way. After a recent upgrade my computer stopped powering off after shutdown.
Thanks to the Rainer Dorsch for pointing me in the right direction.
1. First append this line to your /boot/grub/menu.lst if you are using GRUB or lilo.conf if you are using LILO.
2. Add this line to your /etc/modules
After a reboot, next time you issue the shutdown command your computer should power off automatically.