A new feature that will appear in Call Of Duty Black Ops is the CoD point system.
Weapons, perks, equipment and killstreaks will be bought using the Treyarch's new ingame currency. After you reach a certain level, a weapon or some other piece of equipment becomes available for purchase using the points. This also applies to perks and killstreaks. Perks are unlocked at level 4 and then available for purchase. The same goes for killstreaks which are unlocked at level 10.
This way, if you are not interested in a certain attachment, perk or killstreak, you can completely skip it and save the points for some other purpose.
How will they be earned?
Cod points will be earned both in normal matches (it has been stated that the average player will earn at least 300 CoD points per match) and specially designed game types called Wager Matches. Players will also be able to earn additional points with Contracts.