In my eyes this should react to NPC's ... I missed it in Oblivion, and I think I havn't seen much of it in Morrowind but it was better played out in Morrowind than Oblivion, specially if you did get diseased ... 'You are diseased, you should see a healer' ....
A couple of months back I played Neverwinter Nights with a character of Low Intelligence I dropped on a conversation the NPC directly did react with 'you aren't very smart', or something like that ...
I can Imagine that in Skyrim the AI is pretty much better than in a game of the year 2003 .... I would love to see NPC's react on characters with low Charisma / Personality ... 'mommy that is a ugly one' .... A character with low intelligence 'You want to join the mages guild, hahaah - you can't even speak out you name properly' ....
Give me some thougth about this ....
For that matter there also should be npc's who are lacking in certain parts of there attributes, a npc who isn't very bright, or very strong should be included ...