Now that I've done Gears of War 2 in two late nights straight, played casual just to go thru the story, coz I love to see how things goes, here's a short review of the game:
Casual - Hmm a bit too easy, I think they tone it down so that anyone, including my mom can play, not that she would play it :) Died only twice on the first play thru.
Time to play: Possibly about 12 hours, harder levels may take longer. And I'm not speed running or anything, just love the things they put in the game and casually go thru things slowly.
Story: A bit more drama than the older one. Some downright sad, that did made my wife's heart sink a bit. Ending somewhat similar to the old one. While it concluded that chapter of the story, it's still open for GoW3.
Overall, fun stuff, there are parts that I don't like, and it's exactly the kind of parts I don't like in other 3rd/1st person shooters, which is the riding on something and aim the reticles on moving stuff, with a controller.
Love the achievements target indicator. Shows you how much more of the current things you did in order to get certain achievements. One of the achievements, is Seriously!, in order to get that I need to kill like 100,000 locusts or something, and the game tells you how far along you are to get at that goal.