As a matter of dubiousness which on the edge of dislike: using upvotes and downvotes rather than encouraging conversation.
lol, I knew there would be something I didn't think of to add to the list, thanks. comment upvoted :)
er... wait... did I actually discourage conversation?
Some research says that lurkers make up over 90% of online groups. I suspect that Less Wrong has an even higher percentage of lurkers than other online communities.
Please post a comment in this thread saying "Hi." You can say more if you want, but just posting "Hi" is good for a guaranteed free point of karma.
Also see the introduction thread.