Speaking from experience, while keys are more useful, and more secure if universally used properly - I've seen keys bite firms where it hurts much more often than passwords - because people at some level leave an unprotected key laying around, and that key ends up with root level access to a huge array of servers.
The argument is made, in the article, that if people won't password protect their keys they are equally likely to email their password - but this doesn't ring true - it's more logical and straightforward for people to understand a password that needs to be kept secure than a keyfile, which is more abstract and they may not understand.<p>So - does that mean I wouldn't recommend using keys? No - but if you are going to use them, you have to couple that with strict policies regarding usage and rotation.<p>I use keys for systems where I'm the sole administrator - because I know MY key management practices - but in group situations, we generally stick to passwords as the primary entry point (and then perhaps keys when it comes to accessing clusters of servers - but we tend to treat those clusters as a single functional machine, so keys make sense here)