Historically, suggestion forums are just that...suggestions, mostly to make the community feel good about having "a say". In my experience, the suggestions are rarely considered and even to a less degree implemented. I am not talking just about this forum, but all game forums I've been a member of. A suggestion among thousands might be "looked into" here and there and forumites get all excited and think they are being listened to, but it's usually just to keep the hopes alive.
However, I do agree that suggestion forums are a source of inspiration/bug list for modders.