Occasionally the argument about the affect of aesthetics or beauty on usability seems to come up in UX discussion, and this CHI short paper from 1995 is referred to. This is an article by members of the Design Center, Hitachi discusses the team's research on determinants to apparent usability, based on tests of design and psychology students.
These results show that the apparent usability is less correlated with the inherent usability compared to to the apparent beauty. ... This suggests that the user may be strongly affected by the aesthetic aspect of the interface even when they try to evaluate the interface in its functional aspects and it is suggested that the interface design should strive not only to improve the inherent usability but
also brush up the apparent usability or the aesthetic aspect of the interface.
ACM members can download the short report at the ACM Portal.