One of my first games was Flame War. This was a game that simulated forums such as this; players competed to dominate the discussions.
One of the difficulties was knowing when to score a particular argument. My attempt to solve this was to have a marker showing who had had the last word - if the turn order came back to the player who had last added an argument, then the discussion was scored. This mechanism was a little clunky, but seemed to work.
I eventually put the game to one side because it had two big structural problems. The first was that the game just came down to 'whoever gets into the least fights wins'. The second was that last word mechanism gave a huge incentive to 'mess up the player playing immediately afterwards'.
Looking back at the game now, I think, with the additional experience I have, that I could probably deal with the first problem. I'm finding it difficult to work out sensible ways to score things when they've been idle for a while, though, and I thought that it might be a good idea to throw the question out to others, to see if there were any ways that I'd missed.