I know on some forums I have been on under everyone's name there is a record of how many posts they have and there is even a top 100 of the top posters. The downside is you then often encourage people (kids?) to make dozens of small worthless posts that add little to any real discussions.
Maybe instead it could be based on a formula of number of posts x the score each post gets. Then at the end of each season there could be a "Media Award" for the best posters in each country, or if you want to go crazy, in each division. This shouldn't show up on the front page because it obviously isn't as big as a championship or MVP, but maybe in something like the team history.