SPOILER!!!
Well, as said here, the move is strictly for Doom fans, and only if you have played D3, otherwise, you'd be wasting your money.
Its not scary at all, which is bad since Doom is a creepy game with non-stop nail bitting scares. The movie has an R rating, so why not go all the way with it and make it SCARY!! It does have a lot of the elements of doom. They got the marines characters right, the uniforms, even the setting for Doom3 was right on the money with this movie. The only monsters I saw was Pinky, Ims and zombies.
In the last reel of the movie you actually got to see 1st Person action which was really cool. It looked like the game only on the big screen. COOL. The ending was so bad, though. I fully expected to see The Rock transforming into a Hell Knight, but instead it was lame as it can get.
The movie was like a PG-13 trailer of Doom3.
If you are a Doomer, however, it was worth just going to see all the sets of Doom3 on the big screen. I just can't believe that they messed up by not showing more monsters, NO HELLKNIGHT! And a very poor ending. Instead of a climax, which would have saved the movie, it was lame Ole The Rock turning into something before he gets blown up.