I played a few turns in the tutorial campaign. It plays very much like a Civilization game.
In my first game, I got in trouble with production and got overwhelmed by Necrons. Damn robots are so hard to kill.
Completed the game with Space Marines on Very Easy difficulty (1v1).
I beat the easiest possible game I could set up. The main challenge was dealing with map critters, the Orks proved no challenge whatsoever. I think I'm ready for a game on normal difficulty. Maybe I should get some revenge on the Necrons.