[ericd]

Yeah, I think users should have a limited amount of downvote power to spread around, and that each successive downvote diminishes the power of all their previous downvotes in determining spamminess.

Ghosting really, really sucks for legitimate users. Craigslist does the same thing, and normal people are devastated when they realize they've been judged/victimized by a computer somewhere with no appeal.

[landr0id]

I like the Stack Overflow system of downvoting

  Downvotes remove 2 reputation from the post owner.
  Downvotes on answers remove 1 reputation from you, the voter.
  Downvotes on questions are free.
  You can vote 30 times per UTC day. You get an additional 10 votes on questions only.

On Reddit, people just tend to downvote when they don't agree with something. That's really it. The only times that I've downvoted posts have been when it's a repost from recent, and on comments I only downvote if it's something that's hateful or doesn't contribute to discussion.