Valve has released a title update for Left 4 Dead 2 that they say will address some “rage quitting” issues such as incorrect friendly-fire registration.

Valve has also addressed Tanks and Chargers in Versus mode. On the game’s official blog, the L4D Team writes:

Charger now receives 300 points for any Survivor that is insta-killed.
Charger now receives 100 points for any Survivor that is insta-incapped by a charge.
Any infected that causes a Survivor to stumble into a "ledge hang" situation will receive 50 points.

Tanks go into a stasis when they spawn and leave stasis when the human player takes over.
Tanks do not attack when they are in stasis.
Tanks in stasis are invisible but still show a glow to the infected team.
Tanks in stasis cannot be set on fire.

“We checked some stats, did some testing, checked more stats, and did more testing. We have many more changes we are working on, some ideas failed, some were exploitable, and some were just bad ideas. What we are releasing today is not the sum of our answer to the problem but simply some of the updates that are ready to ship. More are coming.”