Yes human. I summarize articles I find most interesting and would be of interest to the HN community as a whole. As long as I'm up-voted then I'll keep doing it.
I've thought about that. If I see interesting comments I may work it into the summary with a citation. My first choice would be to direct people back to HN for the article discussion.
I'm not sure this is a good trigger. I think you should keep doing it as long as you like doing it, regardless of upvotes.
I would think your server logs would be enough of an indicator of interest.