Hunter of Unreal Fans sent in a link to his interview with professional level designer, Nathan Overman, also known as "TomWithTheWeather". Here's a snippet: 2) Mapping wise how different is it working at Epic rather than say working at home?Since I've been here, I've learned so many little things about UnrealEd and mapping in general that I would have never known otherwise, even from reading tutorials online. My knowledge of the engine and what it can and can't do has increased dramatically just from being in such close proximity to the people who created it and being able to ask them questions. Read the whole interview here.