At the X06 post-conference party, Microsoft showed off the first public (meaning not behind-closed-doors) demo of Gears of War. The over-the-shoulder camera work immediately stands out. By simply shaking the perspective as you move (and shaking it more severely as you run for cover), the game takes on an added cinematic feel unmatched by most other shooters. The shaky-cam doesn't get in the way of gameplay nearly as much as I expected, either, thanks to a well-designed tracking system that follows you around corners perfectly.
Using the A button as an all-purpose run, duck and dive button based on the context makes is a welcome change from the usual mishmash of FPS button functions, though the game did occasionally have some trouble detecting when I wanted to duck behind some pylons. This is pretty key, because the entirety of the single player demo consisted mainly of ducking behind things and popping out to shoot wave after wave of enemies as they pop out of emergence holes. The fact that this pop-and-shoot gameplay doesn't get immediately repetitive is a testament to the enemy AI, which utilizes cover and team strategies surprisingly well, and a testament to the visceral thrill generated by the game's graphics, which are detailed enough to show off every scar on the soldiers' necks.
My only major gripe with the game as it stands now is the ability to come back from the brink of death just by kneeling behind some cover for a short period of time. Between this feature and the frequent checkpoints, the game may not prove much of a challenge for FPS veterans. But the joy of playing Gears of War doesn't really come from the challenge of playing any more than the joy of an action movie comes from the challenge of watching. When everything flows this smoothly, and the details are all handled just right, who cares if you don't have to restart a level 50 times just to finish it?