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Singleplayer
* Vietnam is just a small part of the story. The games story is set across a large period of time.
* Some of the singleplayer maps are based on multiplayer maps, which is usually the other way around.
* In some missions you have the option to move in stealthily or go in guns blazing.
* The enemy AI is smarter. They will now try to dodge if you aim at them.
Multiplayer
* Multiplayer has been in development from day one.
* Lean is back!
* Vehicles will be returning.
* Create-A-Class 2.0 includes deep customization and new features.
* The game will include a "barebones" game mode.
1. As the name implies, there won't be any perks or killstreaks, just old school gameplay.
* Many familiar weapons will be making a return, including the AK-47.
* The region filter is back.
* Improved matchmaking and server browser.
* Modern Warfare 2's host migration will be included.
* Auto-Aim can be turned on/off.
* PC gamers will be able to enjoy the comfort and luxury of dedicated servers.
* The PC version will have an anti-cheat software, but it's unknown if it's Punkbuster.
* There will be support for the competitive community, which will include great tools.
* The team focusing on the multiplayer aspect of the game is twice the size (World at War).
Co-op Mode
* There will be 2-4 player co-op.
* Supports 2 player offline split-screen.
* It won't be based on the singleplayer campaign.
* Zombies might be making a return from World at War.
Miscellaneous
* The game engine is a heavily modified version of the IW engine which was used in World at War.
* The game runs at 60 FPS!
* Physics destruction is going to be limited, so no Battlefield Bad Company 2 style "blow holes in the walls" gameplay.
* The PC version will look better than the console versions (duh).
* There are over 200 people working on Black Ops!
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