Some of the L4D2Center servers have been switched to 128 tickrate. These servers will be active for 10 days, as they are paid until December 18-19th. You can try them out and share your opinion. If you like them, we might create more 128 tick servers in the future (though it's not very likely).

It works like this:

• If a game doesn't start because someone fails to connect, MMR isn't affected.
  
• If a game ends on map 1, the quitter loses MMR. The amount of lost MMR equals what they would lose from a normal loss with a x2 multiplier. Other players neither lose nor gain MMR.
  
• If a winning player quits on map 2 or later (except last map's 2nd round), and the score difference is less than 800, the quitter loses MMR. Other players neither lose nor gain MMR.
  
• If a winning player quits on map 2 or later (except last map's 2nd round), and the score difference is greater than 800, the winning team gains MMR (except for the player who left), and the losing team loses MMR.
  
• If a winning player quits during the 2nd round of the last map, the game won't pause/will automatically unpause. It will continue for 15 minutes to allow the Survivors team to reach the saferoom. MMR will apply to winners and losers as if no one quit, based on the current scores on the scoreboard. If someone from the losing team also quits during this 15-minute period, the game ends, and MMR is applied based on the previous chapter's scores, as if no one quit.
  
• If a losing player quits on map 2 or later, their team loses MMR, and the opposing team gains MMR.

Rage-quitting on the last map when the enemy team is making a comeback (in an attempt to save MMR) won't work anymore: instead of immediately banning the rage-quitter, the server will unpause and give the Survivors an additional 15 minutes to reach the safe room. The ban for the rage-quitter (and any subsequent rage-quitters) will be applied after the game ends.

This will only work if the winner of all previous maps quits during the last map. This will not work if a member of the comeback team quits, or if players from both teams quit.

If a player is in a party in the queue, and one of the party members goes offline or forgets to ready up, and gets kicked from the queue, the rest of the party gets kicked too

Due to a mistake on my part, the MMR of the players hasn't been saved to the database since October 14. I apologize for that. It's fixed now, MMR should be saved properly.