For those who know and played Euro Truck Simulator 2: This is the same developer, so the "basics" in physics and gameplay are similar (Controls and graphics seem to be much better as far as I can tell).
The game itself is different. There is a freeride/delivery-mode as you might know it from ETS2, but it is smaller and, as far as I can see now, less complex (still much fun to play). The ´amazingness´ (Is that a word?) of this game comes from the many modes and missions. Drive along a messed-up road, a mountain pass, or a flooded area (...). This game seems to be the "middle" between ETS2 and 3, to show off what is planned for #3 and what this engine can do.
So, in short:
+runs much more smooth than ETS2
+exciting (!) roads: building sites, narrow bits and tricky obstacles of all kind
+online top-lists encourage competition and motivate to play every mission a thousand times
+very well playable with keyboard, pad or wheel
+not an easy game at all, but not frustrating->If you screw up a mission, you will go out with 0 points unable to compete with anyone online, but you will never get stuck in a mission, forced to do it a million times in order to be able to go to the next one
+++Devs seem to actually read forums and watch videos about their game and listen to the players
-the AI has some minor glitches: nothing game-breaking, more funny
Conclusion: If you liked ETS2, you will love this game even more. It has everything that people wanted in ETS2.
If you have never played ETS and you like to drive trucks in every kind of situation, then this game is something for you.
Recommended .... totally!
Edit: Game seems to crash when doing Alt+Tab, at least for me. Solution: Window mode (which means fullscreen + task bar) or use OpenGL.
Edit²: I found out that this game was released BEFORE ETS2 (Thank you, comments section!). Seems like the fancy graphics have tricked me into some wrong thoughts. ;)