Really all I feel we need to regulate is the blatent keyword/SEO spam and link bait from various online publications. Other than that, I find most of the content on HN hasn't changed all that much from a couple years back when I started reading. There's already a flag button on the interface, but perhaps some kind of spam score or feedback system would help the community point out misleading articles and marketing efforts. I don't know if registered users in the community are the ones from which to demand karma unless they're known to post such links repeatedly.