a cool-enough sci-fi action
Disclaimer: this review concerns the patched version of the game, not the original version.
'Yes', I actually had fun playing it. I've never regarded Cameron's 'Aliens' to be a horror film, its an action film to me. Since this game is based on 'Aliens' I therefore expected an action game, which is what I got. I did not expect, or want, an Amnesia-like horror game. That's not to say Colonial Marines lacks creepy moments, it has those, especially if played alone and with headphones on. The focus is undoubtedly on the action, not unlike horror games like Clive Barkers Undying, Doom 3 or Quake 4.
Regarding the over-arching storyline I don't really care whether every detail in the game matches the films or not, I liked the storyline as it relates to your main character and his team of marines, to me that was more meaningful than the rest. I'm not one of those who expects,or even wants, computer games to be like movies or books. In an action game I want a cool story, good settings, reliable mechanics, and a pleasant combat experience. This game has all that.
I also thought the voice-acting was good, although the facial animations were quite bad. I liked the weapons and the ways you can upgrade them, and how you are forced to choose between different attributes. I like that the game takes you through a wide range of scenarios and environments, as the designs are done really well. The music was also good. My only significant complaint is that the aliens have been "dumbed down" too much on the 'Recruit' level. On the harder difficulty settings they get smarter, or at least more aggressive. That is where the AI becomes good. So play this on a harder difficulty.
I can understand why most people consider ACM a failure since it lacks the superior production quality of a Borderlands game. I can also understand that people who expected a horror game got disappointed since perhaps they view 'Aliens' as a horror film and not an action film. However for someone like me who expected an action game and who is not so picky with graphics, and whether or not the storyline is a 100% fit with the films, this was not a bad game [after the patching]. It's not something I would have paid fullprice for, especially for a ~12 hour campaign, but it's worth picking up if you like sci-fi action and enjoyed the Alien films (note the plural).