Cameron has already taken the time to explain the system well, and it is hardly open to abuse. I agree with you that it stops some people from posting things, not only bad or stupid things as designed (it's good in that respect), but also their honest opinion, simply because they will be voted down. Some people here aren't mature enough to see the difference between someone putting up a good argument and something they disagree with. The karma system should (and in most cases, seems to be) a representation of the way someone acts, not their opinion. Only exception may well be the rant forum, as kesomir said.