Here, you can tell Luke Muehlhauser (lukeprog.com) what you think about his personality, his writing, his personal or professional conduct, or what you think about the organization he works for: the Machine Intelligence Research Institute (intelligence.org). Include your name and contact info if you like - if you don't, your feedback is anonymous!
Luke is a primate, so if you tell him one or two specific things you like about his work, he is more likely to actually consider any criticisms you might have for him.