Yeah, plus new DLC always brings back the new players and L4D might move up to 3rd in players again. Not that it needs anymore, has a really strong population and is really high in the rankings already in number of players per day think 4-5th. Not going to be happy about more 12 year olds coming back/buying the game that scream on the mic and then rage leave when they lose the first map of a versus game, it's like come on.. we got 4 other levels you can make the points up.
My and my friend play all the time together, and l4d has ragers like no other. Well, maybe less than Dota.