Expanding Steam Workshop
Steam Workshop is expanding, adding Serious Sam 3 and Red Orchestra 2 to the line-up of games featuring this community marketplace, allowing users to create and share all kinds of modifications and additions to the games.
Red Orchestra 2 includes access to the SDK, available from the Steam Tools menu, with Workshop integration allowing players to download custom maps and mods. Serious Sam 3 features new weapon mods, skins and maps, with an ability to subscribe to modders who use the Serious Editor.
There is already a wealth of content available for both titles, extending their longevity near indefinitely. Good work Steam, good work.