I'm for asymmetric shame/praise. Worst Nodes should be temporary (e.g. not list All Time Worst but retain Day and Week) in order to keep trolling down as well as give people a chance to recover their reputations after they have been properly "shamed". Whereas Best Nodes should immortalize great nodes as well as give people their temporary limelight.
This is not my idea, someone else brought it up earlier. I do not remember who it was or whether it might have been in the chatterbox.