Gears of War 3 Unlocks

Chrome Skins - past acheivements from gears 1 and gears 2 mostly rank acheivements in both games. ex. Rookie Gear from gears 2 gets you a Chrome Hammerburst. Happy grinding to those who want them all.
Gold Lancer - Own the limited edition and redeem the code from Gears 2
Gold Hammerburst - Preordered Gears 2 from Gamespot and used the code
(No codes were supposed to be sent if you pre-ordered the limited edition from gamespot so the gold hammerburst and lancer were supposed to exclusive of each other, but through various abuse some people have both, not like you can use both at 1 time anyway)
Beta Tester- Play in the Beta test title is featured in multiplayer lobbies so it's a pure prestige thing
Cole Train - Unlock in Beta
Gold Retro Lancer - Unlock in Beta
Veteran Gear Medal and title - Veteran Gear Acheivement in Gears 2
Chars - unlock respectively to how they currently are or beat hardcore for scourge and others from gears 2. *Not all chars may come back*

All unlocks are carry over or acheivement bases, wording in the Beta test didn't include this, but that's how it will be when it releases.