all games are not created equal

Call of Duty 4 was the first game that Infinity ward had published since selling it to Treyarch for CoD3, and I have to say, they did a great job at the come back, not only did the break the expectations of war games to be about World War 2, they broke the bounds that Treyarch had done with Call of Duty 1-3 and World at War.
The game play on both is very similar, but what really catches my eye about CoD4 is the modern day setting, not to mention it was the first of the series to be rated M finally having enough captivation and realism to deserve that title. I also like the maps and online multiplayer.
Call of Duty 4 began many things, such as the shooting through walls, and the perks and leveling system.
However, don't get me wrong, World at War is fun, especially the added feature of blowing people apart and getting to see it happen, certainly making it more graphic.