After spending more than an hour playing Gears of War 2, trying out both its single player and multiplayer modes, I can only think of one thing to say: this game is, quite literally, buckets of awesome. It's that rare game that comes along after several years that you won't easily forget. Gears of War 2 seems to have improved on many of the original's faults. Take, for instance, the cutscenes. One thing notable from the first game is how the cinematics were really choppy, and this really affected the immersion factor. For Gears 2, the cinematics are now really, really smooth; they continue to be real time which improves the immersion but because they're smoother, they're a nice bonus to look forward to when you complete some single player challenges.
Other improvements are more subtle but they're definitely there: gameplay is tighter, the user-interface does a better job of telling you what's going on, and co-op play is implemented more smoothly than it was in the first game. GOW2 is so well polished, and it never feels like a rehash. Presentation-wise, the game screams quality, from the menus to the actual gameplay; the sound effects and music have been beefed up, and when the action gets really heated, the game is a cinematic spectacle. It's cinematic not in the sense that you're sitting there watching in-game cutscenes all the time; it's cinematic because you, the player, seem to be put in a lot of in-game scenarios that feel like something out of a action-packed, special-effects laden, big-budget Hollywood blockbuster.
As for multiplayer, I spent so much time on my first playthrough just enjoying the new HORDE mode cooperatively with my wife. For veteran gamers you'd probably see HORDE mode as essentially GOW2 with bots; but it's the type of 'bot mode' that has never been done right on PC games. There are things on Horde Mode that make it more enjoyable to play over and over again, things like scoring and multipliers which make each run more unique. And it's just something else to play this mode with a friend; once you've finished playing co-op in the single player mode, you have something else to do thanks to Horde Mode.
Later on, the friendly players from Pinoyxbox invited me online to a HORDE mode multiplayer match, and I was really surprised to see that the netcode of the game seems to have been improved dramatically. It's not yet at the level of Halo 3 in terms of feeling 'lag free' but it does feel tighter and making sense of how lag affects your shots is easier to perceive. HORDE mode with four other guys is really enjoyable; it's something else. After a few rounds of the new game mode, there's no denying how much replay value multiplayer can put into a game like Gears of War 2. I've read in other places that some people who have finished it think it is not that long of a game....I can't say yet because I did not rush through the single player campaign (I just picked up the game yesterday). I will say, though, that this game is best experienced as a COMPLETE package when you play BOTH single-player and multiplayer. With multiplayer modes, it's clear to me that this game will last for months on end---you don't measure Gears of War 2 play time in hours, but in months. While playing Horde mode I noticed that some players on my list had some kind of online ranking already, which I suppose they've garnered through multiplayer mode. That just increases the game's value immensely; you haven't played Gears of War 2 until you've experienced everything that the game has to offer out-of-the-box.
The Gears series was built from the ground up for the Xbox 360 platform; there's that story online which says that the reason why the 360 has 512MB of RAM as opposed to 256MB like the PS3 is because Epic Games really lobbied for it, so they can put in large textures for the graphics. It may have made the console more expensive at the outset, but Gears of War 2 really makes you see the benefit of that early decision. I can't think of an Xbox 360 game right now which can stand toe-to-toe with Gears 2 in terms of graphical fidelity. The one effect which I kept on noticing in the new game is how the graphics still look great even if the camera zooms in on a character. In other games, the textures on a character's body seems to lose detail and you can see how it's really just one simple texture. In Gears 2 they seem to be implementing this new effect where, if the camera is close to an in-game object, you see a more detailed set of textures on the object. The way that happens is so smoothly done, I barely notice the transition but I do see how detail increases when the camera zooms in on someone or something in a game. It's one of those rare effects that I haven't seen implemented in other games, whether first person or third person.
If a game really impresses me, I can't stop writing about it. Gears of War 2 is one of those rare games which you could talk about endlessly with fellow gamers. For veteran/hardcore gamers, Gears of War 2 is exactly what the doctor ordered.