HyperVocal has an interesting little article that talks about the demonstratable effect that a font can have on communication. They seem very surprised that it can be proven that a typeface can effect real change in how an audience not only reacts to something, but how they categorize it in order of importance. This is something typographers have known for years. There are real, measurable, effects in both connotative and emotive reactions from the arrangement of letterforms—and not just from serifs or the lack of serifs, but from a number of typographic features. Still, the article is worth reading.