A Steam Community Group Announcement has a release date for American Truck Simulator, saying SCS Software's trucking sequel is due on February 3rd (thanks PCGamesN). They include a reminder that this will launch with just a portion of the full game:

At last, we are ready to commit to an official release date of the first edition of American Truck Simulator; the game will hit digital and retail stores on February 3, 2016.

As the readers of our blog will no doubt know by now, this release will be just the first step on the road. A couple of trucks and the state of California that we are bringing you with the base game release is only a fraction of our grand vision - to cover all of North America eventually and to chase every relevant truck manufacturer for a license to allow us to include their trucks into the game.

Well, we have to set on the way, and this is where we start. Hold on tight!