Valve has released a small patch to Left 4 Dead, getting rid of the melee exploit.
Updates to Left 4 Dead have been released. The updates will be applied automatically when your Steam client is restarted. The specific changes include:
Left 4 Dead
* Fixed an exploit with melee where swapping weapons ignored the intended delay between swings.
* In Versus mode, the Tanks’ health now reflects the damage he takes from burning.
* Fixed an exploit related to the “joinclass” command
Still no word on the new content/SDK release.
