i used to post there a bit more frequently than i do now, but that'll change, depending on how much or how little i have to say.
anyway, i think that if you post a story, and you want comments (and let's face it, everybody who posts a story on the stories board would love to get some feedback), then i think you should make the effort to reply to at least a couple of the other stories that are on the board. i get lazy with this sometimes, because sometimes it takes a lot of effort to read the stories and then come up with commentary that might help the writer, but i try.
it's funny, i workshopped a couple of pieces over on another site, and they make you keep at least a 5:1 review:post ratio, which definitely made sure that everybody was getting some response.
i'm not suggesting that we implement something like that here, but i do think that we could all stand to do a bit more replying on the creative writing boards, even if it's just to tell a writer that we read his/her words.