The consensus among new Unix and Linux users seems to be that sudo is more secure than using the root account, because it requires you type your password to perform potentially harmful actions. In reality, a compromised user account, which is no big deal normally, is instantly root in most setups.

A security hole in Gnome allows anyone to see your keyring passwords without needing to enter so much as a password.

Secure password storage is a big thing these days, particularly with the (good!) advice of not re-using passwords in more than one place. The thinking behind that is that if someone figures out a password for one service or Web site, they will not be able to re-use that password on other sites and further obtain access to your credentials and services.

KDE users however have a built in architecture called KWallet, which is designed to securely store passwords and other sensitive information but also includes integration with KDE (so for example you can have passwords auto-filled, pulled direct from your encrypted, secure KDE wallet).