Bringing the Call of Duty franchise to Modern is a very good move!
The Bad: Campaigns way too short, no 2-Player Co-op.
First off, let me say that Call of Duty 4: Modern warfare is the best game of 2007, easily topping Halo 3 (2nd Best) and paving the way for a new era of realistic, modern war games. It has the most realistic visuals ever seen in a game and has a amazingly good cinematic story that keep you immersed into the gameplay. With that said, let's get this on:
The story and characters are exceptional. Top notch. Not to mention some of the dark moments in the game (ie Character Death) make it a very realistic first person shooter. The only flaw is the game's length make you want more.
The visuals are very impressive such as the prelude mission and the beautiful landscapes. The sound is also top notch. The actors bring the character to life in a sense that you actually enjoy their company and regret their deaths. Not to mention the music and sound effects are pretty good too.
The way the guns react in this game, along with the fact that you cant shoot through certain objects (ie Walls, Wood, Thin Metal Sheeting) and the damage enemies can take make shooting guns very fun. The guns just look great.
The achievements are very good and have you wanting to get them all, not just for your gamerscore, but how cool they are.
The game also offers a arcade mode and the intense Veteran difficulty which extends the amazing fun factor way up.
The multiplayer is also addictive, almost up to the way Halo 3 is. It incorporates the ranking system of Halo 3, but better. The matches are intense with that realistic weapon feel and the character customization classes.
Overall, Infinity Ward has done a amazing job with Call of Duty 4: Modern Warfare. Let's just hope that they will continue to move the series out of World War II and into the great, right direction.