I'm generally pretty suspicious of any sort of computer-generated personality profiles, and though I understand the appeal to techies of empathy-as-a-service I don't think it's something we should consider relying upon.
Hell, half the fun in life is trying to figure out who other people really are.
Imagine how it would affect people commenting if they saw that what they are supposed to post is aggressive, or passive-aggressive ;)
Because you totally need to worry if someone insults you on the Internet.
The ext basically matches my original vision now, so I'm thinking hard about what features to add next, but I'm not quite sure I understand what you're asking for. Are you saying that when the extension says "So and so replied to you", you want, say, a sympathy score shown with that user as well?
For instance: edw519 33 minutes ago | link Top: Cheerfulness, Orderliness, Gregariousness, Agreeableness Bottom: Imagination, Authority-challenging, Intellect
(I'd also something that shows me when a commenter is somebody important, even if not a karma king.)
This could even be true for the follow-feed mechanism. If you're following someone on Twitter or friends with them on Facebook and they write something that appears in your feed, you are already familiar with the author on some level. In the Hackbook extension, it's fairly common to follow people and not know much about them at all. Again, including some basic Watson-generated information along with the "a user you're following wrote a comment" newsfeed item could be helpful.
Let me give it some more thought and maybe I'll have time to work on it this week.
I know the data isn't perfect, but it would be nice to be able see who in a thread is a top HNer and which character traits are outliers from the norm. You get insulted by somebody ranked low in Sympathy? No need to worry.
I'm serious. Somebody do this. It would look great on the résumé.