I've said it before, I don't think posts (or users) should have a number associated to them. It promotes karma whoring. And I don't say that in an accusatory way -- I watch the upvote counts with excitement when I submit a post too. It's just human nature.
If a post was rated "Very unpopular", "Somewhat unpopular", "Neutral", "Somewhat popular" and "Very popular" then you could still identify the hot posts but without engaging the reward/addictive centre of the brain.
Same with users. Don't give them an endlessly growing "karma" number that encourages spamming low quality populist posts. Once they hit "Very popular" there's no more incentive to make submissions purely for the seratonin fix.