ME 2 is ambitious, memorable and well made. Combat falls short, but this experience is still the most fun all year.
Gamespot has most of the mechanics covered, and I agree with everything they've said except the following: Firstly, I found the cover system over-used. They seem to think that hiding behind cover waiting for your shield/barrier to regenerate while enemies fire relentlessly was a good idea, this was BORING. I'm a little impatient, that's why I like COD (I know, I know), and the fact that the majority of combat was waiting did not make combat, and therefore replaying the game attractive. And, wait for it, there is no blindfire, which as we all know, is integral to cover shooters. What could make waiting behind cover more boring? The result is halted action and dead momentum.
Also the feel of the combat didn't work for me. There was no instantaneous connection between what I did and Shepard. The camera was too rigidly locked to Shepard's arms and there was a very artificial feeling to the combat scenarios; cover is placed in obvious places and cliched exploding barrels is the norm, there's no destruction of the environment in sight, and guns don't have the impact they should. Shooting over and around walls is also a bit glitchy. Maybe this is just me and maybe you'll have no problem with it. But I'd advise checking out the demo first for a feel.
The Story was also underwhelming compared to the first game, there was no dazzling footwork at play where everything ties together nicely at the end, and no real shocks and twists (that last part of the game was just wierd). Here, the emphasis is on vast array of characters which plays integral to the emotional impact near the end (hint; people may die). Talking to friends about each's favorite characters, and then discussing their philosophy and morality has been a highlight of this experience. And Mordin is just hilarious. The emphasis on characters makes sense for a prequel to the finale and as a prequel this game works well. The ground works is now set, ready the tissues!!
The main reasons to play this game is the characters, the story and the universe, and these are done with an artistry that could be the pinnacle of video games thus far. The combat is the main problem with the game for me, but it might not be for you. Story is underwhelming, but the universe and characters are so well realized it more than makes up for it. Mass Effect 2 is a very unique game in this market of fast paced popcorn action, and its worth checking out. You'll probably love it,