Well naturally the consumer 'wish list' is definitely something to consider when developing, last thing you want to do is release another run of the mill game into an already saturated market. Wish list aside, its good if a developer listens to the consumer especially with respect to sequels in block buster games. E.g. SC2. Sure Blizzard could go ahead forget everyone and everything and just do what it thinks is best and it'll prolly still turn out fine for initial sales.... cause of the whole cattle effect, however if the controls suck or the features don't live up to consumer expectations especially compared to the many RTS alternatives out there, it would probably not do as well as it could. Now I am in no way endorcing fulfilling every request, however if proper statistical information from your existing fan base for a particular title can be obtained, you can weigh the requests and see what feature sets and improvements are more unanimously demanded by your customer base.
I believe that ultimately the brunt of development and development ideas dose fall on the game house itself however the feedback from ur clients can make or break you imho.