Comment by dang

The old 'saved' list still exists, but has been renamed to 'upvoted' because that is a more precise name. That list is private—we certainly don't want to publish users' votes.

The new 'favorites' list is for highlighting the best stories and comments you see on HN. That list is shared, because want people to browse each other's favorites. The idea is to help disseminate more of the amazing content that people post to Hacker News, much (most?) of which is only seen by a few readers. And I hope that for dedicated HN users it will be fun to curate your own list of highlights, plus see what others have on theirs.

Also if the most-favorited stories and comments turn out to be interesting, we'll publish those lists.