Neither of the two comments (about loot or about bravery streaks) are wrong.  I agree that I don't see where they poll the active player base directly about things as much as they claim "players have said XYZ", however, there might be other/informal communication or data gathering going on.  GM feedback from customer interaction, customer service feedback, forum PM's, turbine devs in groups on Lama or live chatting with other players, or reading comments in threads on the forums, statistics on player activity.  Probably even lurking on the vault and other fan sites/blogs.   

I am in software development and I don't have to officially poll my customer base to figure out what they like and don't like.  Sometimes we do polls, but sometimes we get enough feedback other ways to know what the fuck is up.