Is is just that you don't care enough to reply, feel like your opinions are unpopular, don't feel like you have anything to say, or something else?
Of course, sometimes when reading comments I get the feeling that you people are all entirely, inexcusably wrong, and I feel an urge to set the record straight. Normally on HN, it doesn't take long for someone to step up and explain exactly what I was thinking with an eloquence I couldn't have matched. And the world is right again. :-)