Which usernames do you recognise?
antirez: I remember a few usernames of famous people, people that I know in some way, directly or indirectly, 99% of usernames are new to me every time I read one. This means that basically I (and IMHO most of the HN guys) tend to vote comments mainly by comment quality. Still I believe that it is very hard to avoid to be biased in some way by the ability to read the current comment score.