From the review:
"Clocking in at about 7-8 hours on Normal mode for a person that is proficient at first person shooters, there is never a moment that you wish you can simply skip. Every second you will be on the edge of your seat, wondering what the next room will bring, or how will the story pan out. I can only speak for myself in this regard, and no one else. I was more then happy when I finished the single player campaign, both gameplay and story wise. Without a doubt in my mind, this game is a day one purchase for anyone that enjoys video gaming, and with its robust multiplayer that I have yet to touch, will be one of the games in the upper echelon of Xbox 360 titles."