Some people asked me about why automatic update hasn’t kicked in their Ubuntu Gutsy Gibbon. After investigating, I found out that this problem only affects a small portion of Ubuntu users that perform fresh Ubuntu installation on their computer.
It seems that in Gutsy, the installer choose to enable CDROM package installation by the default and this might has an effect to automatic update. To remedy this problem, you need to go to System->Software Sources and uncheck the “CDrom with Ubuntu 7.10 Gutsy Gibbon” option and check all the other options.
Your will be able to receive automatic update after that!