L4D updated again.  They have some pretty interesting changes to gameplay:

Game and client changes

- [color=red:ddd01af550]Introduced fatigue to the melee attack in versus mode. You will see a HUD display when your melee swing is cooling down[/color:ddd01af550]

- [color=red:ddd01af550]Boomer vomit will now pass through common infected[/color:ddd01af550]

- Addressed some surround sound detection issues

- Fixed a rare crash when exiting Left4Dead on Windows Vista

- Fixed a case where the complete all expert campaigns achievement was not being rewarded

Dedicated server changes

- Corrected an issue where Windows based dedicated were sending spurious shutdown notifications to the master causing them to delist temporarily

- Fixed dedicated servers not resetting the versus team swap correctly--you could join a dedicated server that had a previous game that was swapped and arrive on the other team than what was selected in the lobby

- Renamed the tags for sv_search_key to use &quot;key:&quot; in the server tags instead of &quot;sv_search_key.&quot; This should help with issues of the 63 character limit of server tags

- Fixed an occasional server crash related to voting