Recently got the newest issue of Game Informer, and it has two pages of Gears of War 3 material. At a first read and looking at the pictures this is what I have gathered:
They are taking 6 months to Polish the game. To anyone who has played the other two Gears of Wars, this should be your most favorite part. And so it's first.
Two new game modes:
Capture the Leader: Submission and Guardian at the same time. Players have to protect their leader (unspecified if bot or player) from the enemy team. The first team to Down, Meatsheild, and hold on to the opposing leader for 30 seconds wins.
Team Deathmatch: A new version of Warzone (Warzone is still in the game, as far as I know (It better be, anyway...) ). Both teams have 20 respawns, and when you run out of respawns the game plays exactly like Warzone.
Mantle Kicks: When you mantle over terrain, you kick opponents for a small amount of damage and stun them (Same as melee?)
DEDICATED SERVERS
Digger is a new Heavy Weapon (Morter and Mulcher) that digs underneath the ground a la Bugs Bunny. Direct hit causes the "missle" to burrow into the poor locusts head and explode it.
Pendulum Lancer has a knife on it. "We figured breaking the lore a little would be ok for such a cool game mechanic". Hold B to initiate a "Melee Roadie Run" And if you run into someone you stab them with the knife.
OneShot Sniper Rifle: "The Elephan Gun". A Laser targeted Sniper Rifle. Can supposedly penetrate through Boomshields. Kills in one hit ANYWHERE on the body, but "takes a while to ready a shot".
Sawed Off Shotgun: Have to be really close to instagib instakill (Mantle Kick + Sawsy here is supposed to be a VERY reliable way of killing people).
Gorgan Pistol: Being changed to fully auto SMG. Personally, I hate this, I loved the Gorgan.
Bag and Tag: You can stick grenades to meat sheilds and throw them at enemies.
Incendiary Grenades: Only mentioned in passing, though they say you can "Throw them in the air to rain fire upon your enemies".
Executions are "More sadistic". Racial Executions are in (Cog doing the 3 punch, Locust arm rip and beat CoG to death with it is back in). Every weapon has a unique taunt kill. Bury Lancers into chests, cave skulls in with Hammerbursts, Snap Necks with Sawsy, Flamethrower gets put into peoples chests to cause them to turn into a "Flame belching, charred mess". The Longer the Execution, the more XP you earn for Leveling up.
Leveling unlocks various things now. Instead of being just a number, you unlock things like in
CoD or
BF:
BC. However, it isn't weapon unlocks. You gain skins (Cole's Thrashball uniform is shown, hardly noticable with Clay Carmine being a Bad ass with a flamethrower in the same picture), 2 per character, and....
Mutators are now in. They talk of a mutator turning everyone's head and arms into porportions that are "Cartoony" compared tothe rest of the game. Also, high pitched voices. They are divided into three categories: Make the game harder, make the game easier, and just plain silly.
Speculation: I see three different Female CoGs. One is undoubtibly Anya, another is this (admittingly, rather hot) Brunette, and another really, really pale woman in CoG uniform. As in, Locust Pale

. Can't be Bernie, she looks too young for her, and Alex is a red head, can't be her. There is a picture of a turret with what looks like 4 Pendulum Lancers out in a side by side patern, and what looks like a new pistol (it looks like a tri-barrel revolver, but I can only see half of it. It might be the Boltok, but I have used the Boltok since the first one, and it looks nothing like it.)
Edit: Pics will be up when I find my Scanner.