From ubisoft forums...
http://forums.ubi.com/eve/forums/a/tpc/f/1991064316/m/6751041826/p/1
Questions Answered: Part 1 – Game Mechanics, Weapons & PEC System
Questions Answered: Part 2 – Multiplayer
Questions Answered: Part 3 – Story Mode / Terrorist Hunt
Game Mechanics, Weapons & PEC System
Destroyable Environments – You’ve heard of bullet penetration, but we’ve taken it further. Not only can you shoot through wooden doors and thin walls, you can also break certain objects (such as tables) within the battlefield depending on its durability. See a tango taking cover behind a wooden crate? Shred it and watch them panic, or just shoot them through the box, whatever works for you. You can also damage certain vehicles, some to the point where they even explode. We also give you environmental objects that can help you, such as fire extinguishers which will give off smoke when you shoot them, and combustible tanks. We didn’t place these objects in areas that don’t fit within the environment (I’ve seen other games where gas tanks are placed in the middle of a public street); these environmental tools are found in places that make sense, such as a gas tank under a BBQ grill. Be warned… if the enemy AI spots these objects they’ll use them on you too.
Sprinting - You can sprint for a limited time until your character gets tired. Think of an imaginary bar that depletes itself when you sprint, and slowly begins to fill up again when you don’t. While you sprint you cannot do any other actions, so use it wisely. It’s really handy when you hear a frag hitting the floor. Sprinting uses the Left Bumper (360), L2 (PS3) and Shift Key (default for PC, can be re-assigned).
Other Game Mechanics -
Sorry folks, no “active reload”. Gadgets work pretty much the same. Doors behave the same as Vegas 1 (open and close) with the inclusion of shooting through them/blowing them up depending on the thickness. No melee. Cover system is the same as Vegas 1 but more refined (a lot of testing went into ridding bugs). No “running-man” glitch. No location-based armour (shooting a person’s leg causes the same damage as shooting their arm), however, if your enemy AI is being shot in the foot when taking cover, he’ll actually respond now by moving further back behind cover.
Weapons -
The 11 new weapons are as follows:
P99 (Pistol)
AUG PARA (SMG)
Type 05 JS (SMG)
SKORPION VZ83 (SMG)
FNC (Assault)
L85A2 (Assault)
AKS-74U (Assault)
M468 (Assault)
500 TACTICAL (Shotgun)
L96 Arctic Warfare (Sniper)
SR-25 SD (Sniper)
The “Noob Cannon” (XM-26 LSS) has a slower rate of fire than Vegas 1. Silencers do NOT alert other enemy AI if they aren’t paying attention, which is a major improvement for silencer gameplay. The new SR-25 SD is the first sniper gun with a silencer attachment, making it extra deadly. I can also confirm that silencers DO add extra accuracy to guns but lessens the damage. You can now attach an ACOG Scope on SMGs.
P.E.C. Menu - Improvements from Vegas 1: you can now “swap gadgets” without having to go through the trouble of manually swapping to a different gadget and replacing your current one. Also, you now have 4 slots for custom preset equipment templates: Assault, Recon, Demolition & Sniper. Whatever weapons and gadgets you save on each template will always be there as you freely swap between them. Another great feature is having an auto-save for silencers and rate of fire, meaning, if you have your silencer on in single player, co-op or multiplayer, they will automatically save unless you replace the weapon. You also have a separate equipment template for Story/Terrorist Hunt because you can assign “two primary” guns and a handgun, unlike multiplayer where you assign “one primary” gun and a handgun. Yes, you can now assign two primary guns when playing Terrorist Hunt offline AND online. Last but not least, the P.E.C. menu is not on a separate screen that requires loading. You see the P.E.C. menu as soon as you press start at the main title screen. For those who have played Vegas 1, you will be happy to know that there are no longer 2 loading screens prior to joining a multiplayer map. Loading times have been drastically improved.
For more information, check out the Dev Diary: P.E.C. & REWARDS
http://rainbowsixgame.us.ubi.com/vegas2/index.php
