http://www.steptwo.com.au/columntwo/archives/001138.html
Jared M. Spool has written an article on the using a technique he calls inherent value testing. To quote:
Inherent Value Testing showed us what was valuable about the site and its underlying services. It gives us a concise, easy way to learn how well the site communicates value and where it falls short.
With the results of this technique, design teams can easily prioritize changes. Subsequent testing can demonstrate that changes have improved the design. Inherent Value Testing is one more technique in our user experience toolbox that gives teams the information they need to create successful designs.
(A follow-up article describes in greater detail how to actually conduct inherent value tests.)