Most discussion on Reddit consists of short attacks (or attempts at jokes). There is plenty of that on HN, sure, but a lot of comments are pretty long explanations of what the poster thinks. I don't find this to be sterile (and I enjoy not knowing about Internet memes anymore).
Interestingly, most of your comments here are significantly longer (and more insightful) than those at Reddit. I think it's because you are replying to comments here with actual substance, whereas on Reddit most of the comments are mindless and don't leave much for you to say. I think this is a sign that HN is doing well, or rather, that it works the way I like. (That's why I spend my time here now, rather than on Reddit.)
