Okay...
As a reader I do appreciate when the author takes a little of his/her time sending some counter-FDK (as I call it.) well, I do waste my time there sending them my impressions, but I do understand some don´t have the time (probably busy writing YAY!!!) to post something else.
As a writer, I usually reply to every suggestion, question or comment the reader has. Basically because I am always happy my stories were actually read by anyone.
Er.. I don't have many fans <sighs> but the ones I have are very well treated, right stupidbraz' fans?