I think there should be a review of the karma system. I was browsing through the top contributors page and it turns out someone whose best comment is on the lines of please vote for me because I need karma to ask a question is on the first page for top contributors for discussions. This is unfair to those contributors who write editorials and tutorials and occasionally get fewer points than people requesting upvotes on their comments so that they can ask a question.
I think that the following system should be implemented
Give all users the minimum basic karma required to ask a question
Divide comments into categories like tutorials/editorials, helpful links, opinions and irrelevant comments/spam.
Give the highest karma to users who write well written tutorials/editorials and point to helpful tutorials and a reduced
formkarma to opinion based comments
Block people from further posting if they post irrelevant comments and spam.