Left 4 Dead 2 Getting Steam Workshop
The Steam Workshop is a tool that allows players to create and browse community content more easily. This tool is now coming to Left 4 Dead 2. The Steam Workshop for Left 4 Dead 2 will have some mysterious new features that will “allow content to appear in the L4D2 world even more seamlessly based on the community’s response”. Valve will also be releasing a new scripting tool that will allow the community to create its own mutations. These mutations can also be made available in the Steam Workshop.
Source: Left 4 Dead Blog