Some of this is confirmed, some of this is not. Taken from CoD Wiki
* Vehicles will return, but they will be very different than those in Call of Duty: World at War.
By vechicles I hope they mean killstreaks, not tanks. (Tanks weren't that bad they just too 2-3 lives to kill, way to strong) However that would be pretty cool if tanks and such could shoot them down.
* Black Ops will feature a dedicated co-op campaign, supporting up to four players, which uses different levels than the singleplayer campaign. When asked about zombies in an interview, they stated that they could not talk about the co-op campaign, hinting that it will be a zombie campaign.
Not much to say about this, except for the fact that co-op didn't work out the best in WaW except for zombies. It's really a no-brainer that it will be in Black-Ops as zombies is what held the game up and the fact that Activision swam in money after the 3 WaW DLC's.
* Treyarch is considering releasing a beta-build test, and has hinted that it is likely.
Public Beta!!! I'm pretty sure some problems were fixed in the game when the WaW beta was out. I also think MW2 would be improved if they had a public beta.
* Matchmaking is being changed so that it is easier for friends to play together.
I'm not sure if this means playing with people on your friends list or by making local search non-optional.
* 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.
This is good because of the fact that Treyarch can do whatever the hell they want with their maps and not feel like they have to base it off campaign.
* Create-A-Class 2.0 will allow players to customize their appearance in addition to their loadout.
I think this would be extremely cool along with the fact that you should unlock things for your appearance just like RSV2, except 1960's style.
* Customized killstreaks will return, but the game-ending Tactical Nuke will not. Kills earned from killstreak rewards will not count towards increasing a player's killstreak.
I mean this goes both ways. Mainly the positive way because you still have the option to get killstreak rewards even though they won't overpower the sky for the other team.
* The Call of Duty: Modern Warfare 2 perks, Commando and One Man Army, are not going to return.
Yay, listening to the community.[/quote] Yay, they are listening to the community!
* The PC version of Call of Duty: Black Ops will feature dedicated servers.
I know it would be a lot for them to have Xbox Live + PSN dedicated servers but damn I wish they would.
* Shotguns and Machine Pistols as secondary weapons are not expected to return, as Treyarch stated in an interview that they give the player "too much firepower".
One of the biggest problems for MW2 will be solved, because its just way to much having someone rush your spawn spraying with a UMP then just wiping out a SPAS and not even having the option to get a shot on them.