Sorry for double post, but I'll just copypaste everything what people have found in
CoDwiki.
General * Highest level of rank is level 50 and prestige mode is still in online ranks.
* Vehicles will return, but they will be very different than those in Call of Duty: World at War; some are now killstreaks as opposed to map items, such as the Chopper Gunner.
* Some campaign levels will be based off multiplayer maps instead of the typical vice-versa. This change is because some multiplayer maps had been made before the campaign was finalized.
* The PC version of Call of Duty: Black Ops will feature dedicated servers. [10]
* Players can now record, manage, edit and upload in-game video clips to their file share via "theatre mode."
* Matchmaking is being changed so that it is easier for friends to play together.
* In-game currency will be used to purchase weapons and upgrades.
* In the Black Ops rank system, the player must level up to unlock weapons for purchase.
* Split screen online for the Xbox 360 has been implemented.
* Unlike in World at War, submachine guns will have full movement speed while aiming down the sights, as they did in most other Call of Duty games.
Confirmed Multiplayer Maps * Summit
* Launch
* Radiation
* Cracked
Gametypes * Team Deathmatch will return; however, points for headshots and other bonuses will be added to the team's score.
* Capture the Flag
* Search and Destroy
* Demolition
* Hardcore Team Deathmatch
* Headquarters
* Sabotage
* Domination
* Combat Training: Fight against enemy AI in a training mode.
CoD PointsCoD Points are a new major feature of Black Ops. CoD Points will become the new in-game currency and will allow players to buy weapons, attachments, and Contracts. In addition to this, players are also allowed to wager these points in certain game modes.
Contracts
Contracts are a new system in addition to the classic challenge system in Black Ops. A player is able to buy a contract with CoD Points, which will then direct them to complete an object. Completion of a contract will yield a higher CoD point payout than what was originally paid for the contract itself.
Wager Matches
A new mode with a separate ranking structure than the standard online modes, will allow players to gamble with their money. However, only the top three will receive the prize. They will be placed into one of four random modes:
* One in the Chamber - each player is given a pistol with one bullet and a knife. For each kill achieved the player will receive one more bullet. However, each player will only have three lives.
* Sharpshooter - each player is given the same random weapon. The weapon will be used for 45 seconds before being switched out for another one. Kills will award the player with perks and score multipliers.
* Sticks and Stones - each player receives only a crossbow, ballistic knife, and a Tomahawk. The catch in this gamemode is that if the player was able to hit an enemy with a Tomahawk, the enemy player will go "bankrupted".
* Gun Game - players start out with a pistol. For each kill they move up a level, granting them a better gun. First person to achieve kills with all 20 weapons wins. However, someone who is knifed will move down a level.
Create a Class * Create-A-Class 2.0 will allow players to customize their appearance in addition to their loadout. Players may see what their character looks like while choosing a class, as the player's basic appearance will be determined by their Tier 1 Perk. Players will also be able to choose a Facepaint pattern.
* Some sights such as the Red Dot Sight can use custom reticules which includes choice of shape and color.
* Gun camouflages will be featured in Black Ops and will be far more numerous than in previous Call of Duty games.
* Players' clan tags are engraved onto their guns.
Perks of Call of Duty: Black OpsTier 1 Perks Lightweight · Scavenger · Ghost · Flak Jacket · Hardline
Tier 2 Perks Hardened · Scout · Steady Aim · Sleight of Hand · Warlord
Tier 3 Perks Marathon · Ninja · Second Chance · Hacker · Tactical Mask
Killstreaks * 3 kill streaks: Spy Plane, RC-XD
* 4 kill streaks: Counter-Spy Plane, SAM Turret
* 5 kill streaks: Care Package, Napalm Strike
* 6 kill streaks: Sentry Gun, Mortar Team
* 7 kill streaks: Attack Helicopter, Valkyrie Rockets
* 8 kill streaks: Blackbird, Rolling Thunder
* 9 kill streaks: Chopper Gunner
* 11 kill streaks: Attack Dogs, Gunship
PC-only information * The PC version of Call of Duty: Black Ops will feature dedicated servers.[11]
* Modding tools and the leaning feature will return, though it is likely that the modding tools will come out a bit after the game has been released.
* The PC version will be using Steam as DRM and will be using VAC as an anti-cheating tool.
* Players can choose a server via a server browser screen or use matchmaking to send a lobby to a server chosen by the game.
* Dedicated servers must be rented.
* Unranked servers are completely customizable while ranked ones let the renter choose levels and gametypes.
Console-only information * Treyarch has confirmed that it will be close to impossible to use any kind of mods in Call of Duty: Black Ops.
* Matchmaking is being changed so that it is easier for friends to play together.
Assault Rifles * M16
* Enfield
* M14
* FAMAS
* Galil[12]
* AUG
* FAL
* AK-47
* Commando
* G11[13]
Submachine Guns * MP5K
* MAC-11
* AK-74u[14]
* Skorpion
* Uzi
* Spectre M4
* MPL
* PM-63
Light Machine Guns * RPK
* M60
* HK21
* Death Machine
Sniper Rifles * L96A1
* Dragunov[15]
* WA2000
Shotguns * SPAS
* KS-23[16]
* Stakeout
* HS-10
* Olympia
Pistols * M1911
* Python
* Makarov[17]
* ASP
* CZ75
Launchers * RPG-7
* China Lake
* M72 LAW
* Grim Reaper
Other * Crossbow
* Ballistic Knife
Attachments * Extended Magazines
* Dual Mag
* ACOG Scope
* Red Dot Sight
* Reflex
* Masterkey Shotgun
* Flamethrower
* Infrared Scope
* Grenade Launcher
* Suppressor
* Swarovski Scope
* Snub Nose
* Flashlight
* Dual Wield
* Speed Reloader (Python only)
Alternate Ammo Types * Dragon's Breath
* Explosive Bolts
Weapon Camouflages * Dusty
* Ice
* Red
* Olive
* Nevada
* Sahara
* ERDL
* Tiger
* Berlin
* Warsaw
* Siberia
* Yukon
* Woodland
* Flora
Equipment * Jammer
* Motion Sensor
* Tactical Insertion
* C4
* Claymore
* Camera Spike
Tactical Grenades * Willy Pete
* Nova Gas
* Flashbang
* Concussion
* Decoy
Lethal Grenades * M67
* Semtex
* Tomahawk
As you can see, the weapon list is now much larger then it is in my first copypaste. I'll edit the opening post.