In a long update on Digg the Blog, Kevin Rose announced that they have decided after long internal talks to remove the top diggers list. They have decided to do this because of people trying to game digg. The only way they could finally put a stop to this is to remove the list of people that were getting offered payments by others to get their content in the front page. If the people can’t find the highest diggers then they can’t offer payments to them.
You can check out the whole post here.