The most impressive thing that Activision had to show, by far, was their surprisingly intense Call of Duty 4: Modern Warfare demo.

The demo, which mixed cut-scenes with some actual gameplay, left me feeling more than a little shaken and jonesing to get my hands on the game. The most important thing you need to keep in mind about this game is that Infinity Ward is developing it. So, it's gonna kick ass.

The game seems to do several things very right. It updates the graphics and the look of the game, doing an excellent job of capturing what I suspect the feel of modern combat is. It also keeps that addictive pacing that made the first two Call of Duty games so very much fun to play and hard to put down.

The game will feature to main story lines both of which center around a Russian warlord of some sort. More importantly, the game seems to mix up the action quite a bit. Instead of forcing you to stay on the ground, grunting it through the levels, you get to do things like take to a Cobra Gunship as a gunner, take on covert missions, even board planes to remotely take down targets from quite a distance.

The development teams say they've been working on multiplayer for the game since day one because they realize just how important it is to the game's longevity. One of the cool features built into the multiplayer mode is that you can unlock aspects of the game (like weapons or character classes) by playing online. The online mode will also feature create-a-class so you can create the exact type of character you want to play online and save it.

The game also brings back the killcam, letting you watch the 15 seconds that led up to your death, after you get taken out.

I can't wait to get my hands on this game. I can tell it's going to be the sort of title I'll have to set time limits for myself before I play.