Usability standards are not established by a person or place, but it is what is adopted by the user community at large. It is difficult to change or establish new standards, but it is more important for usability to follow standards that are studied and identified by usability experts, such as Jakob Nielsen or Steve Krug.
One must establish what 'look and feel' works best for the end user, or target market. The purpose is to strengthen the brand, not necessarily try to design something that everyone is going to like. That's impossible to accomplish, it's just too subjective. It is better to instill better usability as a standard and use colors and graphics that are compelling but are not overstated. Always think of the old saying "form follow function."
They provided a sheet of paper that had a fake Battle.net website on it. They asked me to circle all of the defects that I could find. They also asked me to solve a fairly simple math equation with one simple rule and that I would "bet my job" on the answer being right.
I was able to find all of the defects. It was fairly easy to find them, but you need to have an eye for detail (i.e. look at the URL in the address bar in addition to the page itself). As for the math question, the simple rule was "I couldn't use my own cell phone's calculator to solve the equation." I simple asked if I could use someone else's phone and they said that was fine. I double-checked the equation on paper to make sure the phone wasn't intentionally programmed to give me a wrong answer.