Here is a full list of the weapon skins, character unlocks and future downloadable content.

COG
*Marcus Fenix
*Dominic Santiago
*Augustus Cole
*Damon Baird
*Anya Stroud


Unlockables
*Jace Stratton
*Dizzy Wallin
*Samantha Byrne
*COG Gear
*Cole Train (Unlocked in Beta)
*Clayton Carmine-Reach Level 14
*Classic Marcus-Earn Silver Veteran Medal
*Classic Dom-Reach Level 17
*Classic Cole-Reach Level 23
*Classic Baird-Reach Level 30
*Civilian Anya-Reach Level 45
*Unarmored Marcus-Complete the campain on any difficulty
*Benjamin Carmine-Reach Level 34
*Superstar Cole-Earn Gold MVP Medal
*Aaron Griffin- Unlock Via Facebook (Like the Gears of War 3 Page)
*Chairman Prescott-Earn Silver Allfathers Medal
*Victor Hoffman- Reach Level 50
*Anthony Carmine-Reach Level 75
*Golden Gear-Earn Bronze War Supporter Medal

Locust
*Drone
*Savage Drone
*Grenadier Elite
*Savage Grenadier
*Queen Myrrah

Unlockables
*Locust Miner
*Beast Rider
*Theron Guard
*Locust Hunter
*Savage Theron Guard-Complete 12 waves of Beast Modeall difficulties
*Locust Spotter-Reach Level 20
*Flame Grenadier-Reach Level 26
*Kantus-Earn the Gold Medic Medal
*Sniper Drone-Earn the Bronze Headshot Medal
*Grenadier-Reach level 39
*Golden Hunter-Earn the Golden Master-at-Arms Medal
*Golden Miner-Earn the Gold Rifleman Medal
*Hunter Elite-Reach Level 60

Downloadable Content
*Bernadette Mataki
*Onyx Guard
*Tai Kaliso
*Minh Young Kim
*RAAM
*Skorge
*Michael Barrick

Exclusives
*Mechanic Baird (Bestbuy Pre-order Exclusive)
* Adam Fenix (Exclusive to Limited and Epic Editions)[9]
* Commando Dom (GameStop Pre-order Exclusive)
* Savage Kantus (Amazon.com Epic & Limited edition Pre-order Exclusive)
* Savage Grenadier Elite (Wal-mart Epic & Limited edition Pre-order Exclusive)

Weapon Skins

Flaming Hammerburst - Unlocked if you played the beta between April 18th and April 24th

Flaming Lancer - Unlocked if you played the beta between April 25th and May 1st

Flaming Retro Lancer - No information at the moment...

Flaming SOS - Unlocked if you played the beta between May 2nd and May 8th

Flaming Gnasher - Unlocked if you played the beta between May 9th and May 15th

Gold Lancer - Play Gears of War 3 online between September 20th and September 27th

Gold Hammerburst - Play Gears of War 3 online between September 20th and September 27th

Gold Retro Lancer - Unlocked in beta (complete 90 matches and get 100 kills with the gold Retro Lancer). Can also be unlocked by getting Veteran Gear in Gears 2 (reach level 100 and win a match on all four Snowblind Maps)

Gold Gnasher - Unlocked by getting Veteran Gear in Gears 2 (reach level 100 and win a match on all four Snowblind Maps)

Gold SOS - Beat Gears of War 1 on Insane

(NOTE - Veteran Gear unlocks the gold skin for all five starting weapons. However, the Gnasher is exclusive to VG)

Chrome Lancer - In Gears 1, finish a ranked match with the highest amount of points.

Chrome Hammerburst - Complete 10 waves of Horde, on any difficulty, on any map, in Gears 2

Chrome Retro Lancer - In Gears 1, complete 10 different co-op chapters as Dominic Santiago on any difficulty

Chrome Gnasher - Complete the campaigns of Gears of War 1, 2 and 3, on any difficulty

Chrome SOS Have at least one achievement from Gears of War PC (doesn't matter which one)

Onyx Lancer Get 6000 kills with the Lancer in Gears 3

Onyx Hammerburst Get 6000 kills with the Hammerburst in Gears 3

Onyx Retro Lancer Get 6000 kills with the Retro Lancer in Gears 3

Onyx Gnasher Get 6000 kills with the Gnasher in Gears 3

Onyx SOS Get 6000 kills with the SOS in Gears 3

Gold Omen (all 5 starting weapons) - Reach level 100 in Gears of War 3

Infected Omen (all 5 starting weapons) - Included with the Gears of War 3 Epic Edition, limited edition console or limited edition controller

Liquid Metal (all 5 starting weapons) - Included with the Gears of War 3 Season Pass

Liquid Green (all 5 starting weapons) - Obtained (for free) through a yet to be announced promotion

White/ Ivory (all 5 starting weapons) - Exclusive to Epic employees or those who are close friends with Joe Graf.

Joe Graf is a great guy by the way .