Software developers always have to be mindful of avoiding Gold Plating. Developers, though, are not the only team members that can go overboard on a project or feature. When visual designers use aesthetics to emphasize “beauty” over usability, they overstep their duties to the users of their software.
One tendency I see now is to over-use the color gray throughout an interface–John Brandt discussed this in his post What’s with all the gray? I propose the phrase “Gray Plating” (or “Grey Plating” if you prefer the non-U.S. spelling) for the overuse of this visual style when it is detrimental to the user experience.