I just found the paper by Halford and Hsu, that describes the effect that the appearance of companies' CEOs have on the stock value of said company after public appearances of the CEO. They were able to confirm the correlation and gave sufficient evidence to suggest causation.
Even though the scientific community tends to think it soars above the normal, human things that people do or concern themselves with, being human beings comes with its set of deficiencies. I have tried to find articles that try to analyse the impact of conference talks with respect to the appearance of the person giving the talk, but my searches came up empty.
I cannot believe that we are able to fully dissociate content and appearance (this goes for written communication as well) from each other to come to a neutral, unbiased judgement about the content.
I am interested if there are known cases of bias of the scientific community in general, and possibly your discipline in particular, which value the contributions by their peers differently, depending on how they look.
Basically, since the question in the title is rather broad, it boils down to this: Is there correlation between beauty and citation count? If someone can dig up a paper that describes and checks this, I would be grateful.