You know there's a lot of modern gritty shooters out there -- it's a major trend in video gaming right now -- and even though I do intend to play a number of them someday, they tend to be on the bottom of my list of desired games because they're mostly the same not only in terms of gameplay, but also visually.
Gears of War is completely different.
It only took a few moments of watching video of Gears of War 3 to badly want to play the game and the series in general. It's hard to put into words what I noticed about it, but it just seemed to be a much more impressive and dynamic experience than most shooters. The storyline seemed to be really well-executed and integrated smoothly into the missions, continuing even while in the middle of playing; the levels seem like really realistic, dynamic scenes in an action story. Emphasis on story, because all your squad mates are talking and interacting even as you're playing and shooting monsters.
The cover system really got me as well. You can get shot down but the game tends to forgive that as long as you're coordinating with your team (because they'll revive you), and the emphasis on using cover is excellent, because for a long time now I've wanted to see a shooter that mimics the feeling of a realistic shootout, where cover is vital to survival. It looks like the Gears games do just that, while still allowing and rewarding judicious aggressive advances. This all equals a far deeper shooter experience where it's not just about running and gunning (which is fun as hell but a lot more shallow), but about tactical maneuvers.
It looks like an excellent design for a shooter and while I've yet to play a Gears game, I'm very, very interested.