Well i think it's free to speak about this game now.
This article contains Spoiler.

1- Story
Typical, just like the first game. the only thing that added to the plot is some drama things in it- for example (Spoiler goes) Dom's Wife named Maria, who is taken as prisoner  by Lucasts. we will find her near a lucast stronghold, and soon she turns into a hag, or undead, i don't know- and Dom draws his pistol and kills her. also a civil war(?) started between glowing lucasts and ordinary lucasts, you will discover it while looking for the queen of Sera. nothing Fantastic though, Gears of War is very similiar to Halo in story ascepts.

2- Gameplay
You ever heard of a dreamcast game named "Kill Switch"? you should know that Barricade system of this game is followed by Gears of War series. i saying it because some people think Gears of war "Created" this idea about possibility of blindfiring when you are hiding behind a barricade.
But Gunplay is Improved, Five new weapons, Containing a Missile Launcher, A portable turrent, a SMG like weapon, a flamethrower and and a machine gun with single fire shot.
The Best part of game is riding a Giant Bumark.

3- Technical
Graphics have nothing to say, among with Physics and Interior Design of game. NPC AI is better than the original game somehow.

Enough speaking,

Cheers