Because our Devs are already hopelessly overloaded with feature requests.
Yes I am aware how easily this could become "Request A Feature" thread. I think the devs we have do a fabulous job and do not want to pound on them.
One wonderful thing Brion has done recently is get the Foundation signed up for the Google Summer of Code. Let's make sure the community tells the devs what is important to us. There are a list of possible projects at
http://meta.wikimedia.org/wiki/Summer_of_Code_2006
Pete