I can't help but think that Hacker News has made several design decisions that are geared specifically to keep people coming back over and over and over again.

I can't help but think that Hacker News has made several design decisions that are geared specifically to keep people coming back over and over and over again. Some that come to mind are not notifying you when someone replies to you, not having feeds for comments on a story, and not having a feeds for the beststories or bestcomments pages.