HN News lacks two features that are predominant in social network site: follow people and like postings. I would not call HN News social networking. I'm hoping HN News can add like/favorite feature so that I can bookmarked posts/discussion right within HN News.
wouldn't upvoting a story be considered the same as liking a post. Then go to your profile and view saved, then you can view posts you liked. Also comments in your profile you can view discussions you participated in.
I would also suggest that "liking" isn't a feature necessary to call something a social network. ie Myspace, Twitter (favourites perhaps?), Linkedin etc
