i like threaded boards.
if you look at GFY as an example, you know who certain people are and who you would be interested in hearing what they say and who you would not be... you can go right to what threads, posts/topics interest you.
i think that flat boards also discourage a lot of people from posting because it can be a little intimidating to say something knowing that all eyes are on you.
the bananas are happy.
in the end, thats all that matters