Do we have any metrics on liveness of accounts? I've certainly felt that the community of active, thoughtful commentators is pretty small (not a bad thing!).
[1] http://web.archive.org/web/20050414040411/ycombinator.com/sfpannounce.html
lynx -source http://news.ycombinator.com/user?id=$USER_IN_QUESTION | grep '<span class="comhead">' | wc -l