Several folks who commented on my "Pandora, Pop Culture and Philanthropy" post fall into this category so I want to draw your attention to this note, on three types of recommendation structures:
"I think that different people (or personalities) seek out different types of recommendations.Words to the wise for the data discussion and those considering building recommendation engines or models to guide donors.
I'd say there are about three types of recommendations that people look for, Expert (a professional reviewer), Social ("hey, my buddy really liked this"), and Managed (radio plays and automated recommendations). The best resources will be the ones that offer all three." (Thanks, Aram ZS)