I disagree. If a sticky thread is made showing things that have been made before as well as what has gained ground and what hasn't, it is less likely that the noobs will come strolling in demanding things that we know to be pointless. It creates the possibility (however slim) that repeat topics will not show up and that the wishlist section would only be of new ideas for the game not the same crap over and over.
We can all think of at least one topic that has come up several times, I can think of one in particular that has a habit of popping up every month or so. I'm sure there are a few people who have held off on posting an idea or a wish because they were afraid it had already been asked for. I have done this myself a few times because I am trying to maintain a (low) level of credibility. The wishes I'm thinking of are difficult to search for, so it's hard to know if someone has asked for it before or not.