I was told that listing all the imports individually slows down compilation or execution, not that this makes much sense. I'm not sure how reliable the source was, and never tested it, but I've taken to condensing the imports manually in my Eclipse environment. Am looking forward to the definitive answer, and am too busy/lazy to try and figure or test it out myself. Just tell me what to do. (I've got a lot else on my plate, thank you.)
ra4king's statement about the compiler being smart enough not to load unneeded code has a ring of truth to it.