Take a look at the first multiplayer teaser for the upcoming Call of Duty: Black Ops by Treyarch.
One of the greatest features this video reveals is the ability to record your gameplay, just like in Halo 3, Madden and very, very few other games. This works great for a lot of people, tough does not matter myself as I will still obtain better quality by using my HD-High Definition Capture Card instead.
You will notice a LOT of similarities to Modern Warfare 2 which is expect by the same engine and Treyarch needs to keep up with what people want. You will also notice a few new killstreaks, such as the RV bomb by just killing 3 people without dieing or possibility 2, if Treyarch has a Perk related to Hardline or not.