First of all, there is a big possibility that after you install the demo, you going to have problems launching the game.
There are going to be error message. To fix that problem all you will have to do is rename a file located at
C:Program FilesActivisionCall of Duty 4 - Modern Warfare Demomiles
Rename the mssmp3.asi file to mssmp3.bak.
After that, the game should run perfectly.



Here is the specifications made by COD team:

"Recommended Specs"

CPU: 2.4 GHz dual core or better is recommended
RAM: 1G for XP; 2G for Vista is recommended
Harddrive: 8GB of free hard drive space
Video card: 3.0 Shader Support recommended. Nvidia Geforce 7800 or better or ATI Radeon X1800 or better




"Required (Minimum) Specs"
CPU: Intel(R) Pentium(R) 4 2.4 GHz or AMD(R) Athlon(TM) 64 2800+ processor or any 1.8Ghz Dual Core Processor or better supported
RAM: 512MB RAM;768MB for Windows Vista
Harddrive: 8GB of free hard drive space
Video card: NVIDIA(R) Geforce(TM) 6600 or better or ATI(R) Radeon(R) 9800Pro or better



I will be testing it on
CPU: AMD XP 2500+
RAM: 1 GB
Harddrive: 25GB Available
Video card: Nvidia(R) Geforce(TM) 6800



As you can see, my compute is pretty slow for that game, yet I was able to play the game pretty smooth.



So, about the game:
Can't say about graphics as I played on low video settings, but graphics was pretty good on that settings too.
The game is very realistic. If you get shot couple times screen will turn red and you may survive if you go to safe area and rest for couple seconds.
Now, instead of listening to your comrades, there is radio and you can clearly hear many different navy conversations. It was pretty nice to see Automat Kalashnikova (AK-47) in Call of Duty game. You are allowed to switch weapons. Reloading weapons looks very realistic. Unfortunatelly the demo was only 5-10 minutes long, so there is not too much to say. The call of duty 4 will be released in just couple weeks, so the next review will be a lot bigger! Stay with us!



Update:

Finally, I was able to make a video of the demo, so if you have good internet speed, you can take a look at the demo: