One of the most original shooters out there. Plus all the goodies to make it one of the best.
Sound: Is great. The effects of walking, shooting, running into things, water, ect. is awesome. The music in the game, i.e. random record players playing, totally add to the creepiness of the atmopshere. Gameplay: Smooth and full of action. Hearing the splicers laughing and talking to themselves before you can see them makes for some intense moments. I haven't checked out online play or beaten the game so I can't speak for replay value.
Anyways, I think this game rivals, or is better than Gears of War, as far as the single player mission goes. The 50's style is honestly my favorite part. The look and feel of the game makes it that much better. Do yourself a favor and rent, buy, or steal this game for yourself. Its the best out there right now.