I bought Call of Duty 4.
I have beat Call of Duty 4.
In 5 hours.
thats $60 for 5 hours of entertainment.
Now dont get me wrong...the game was absolutely stunning and quite possibly the best I've played.
But seriously...a 5 hour single player mission? I realize that a good chunk of the people that purchase this product, do so for the online play. But I don't play online.
so yeah...short but sweet.

MINOR SPOILERS AHEAD!!!!!
The graphics, as advertised, were brilliant:
 
and the warfare immersion was incredible. I truly felt overwhelmed by the chaos of battle.
What's truly great about the game is that you're just not one dude running around with a machine gun wasting everything that crosses your path. In fact, in one 'episode' you're the gunner of a C-130 Gunship. If you've ever watched videos like the one below on YouTube:

You'll be happy to know that the gunner portion of the game is nearly identical to these in flight video. The in game dialog is perfect for each of the various scenarios that you'll find yourself thrown into. And you'll also find yourself in a few 'holy crap' moments of awe during the game. Most notably the nuke scene. I wont ruin it for you, but when it happens you'll understand what I mean. 
So go buy the game. But keep in mind that its short. AND you'll want to be aware that this game is NOT kid friendly. Some of the earlier COD titles were borderline o.k. for young gamers, however COD 4 is NOT. There are quite a few instances of in street assasinations and group massacres that would raise parental eyebrows. In fact, during one cut scene you actually play the role of someone that is strapped to a pole and shot point blank in the head. So play and let play at your own risk. 
Overall..one of the best games that I've played in quite a while, if not the best. And who knows...maybe you want a short single player mission. In hindsight, its probably best that I could get in and out of the game in such a short amount of time. I have a ton of things to do this month and game time is a commodity. Speaking of being busy....back to it.