One thing we need if it stays is a top karma list and possibly a bottom list too if negative karma is possible. You can't keep up with the Joneses if you can't see where they are. It would be quite amusing if one person topped both lists.
This forum definitely needs more pointless stats to look at, how else are we to tell ourselves we are winning?
Personally I would suggest it is more of a way to indicate the relative merit of various posts although it isn't really set up that way. Because it is called karma it should not be perceived as a pure popularity vote, the name implies you get what you deserve. Applaud good ideas and smite trolls. Unfortunately trolls will applaud trollish behaviour but as the Buddhists say "all life is suffering."