Let’s start with the things people probably will not want to see, juggernaut has always been unpopular, therefore there will undoubtedly be many readers out there hoping that it will not be a perk option in Black Ops.
My two biggest hates in MW2 are long range handgun kills and the combination of marathon / lightweight / commando and tactical knife. I have seen people get extremely long range kills with the Magnum, despite its low accuracy stats, also I have been stabbed so many times by people that move faster than Usain Bolt.
I would love to see some sort of distance covered stat when you finish game, this should end the endless camping arguments, perhaps Black Ops could give you a higher score multiplier for the more distance you cover.
In my opinion claymore mines are not affective enough in MW2, once you have mastered them they are great, however when compared to bouncing betty mines used in World at War they are far less effective, surely modern weaponry should be more effective than older kit.
Nube tubing is in my opinion a big problem in MW2, therefore I would like to see Black Ops perhaps take some sort of action against it, perhaps only allow you to nube after 15 seconds from spawning, or just make nubes less accurate.
In some Ghost Recon games you were able to put markers on the map for other players on your team to see, I would love to see something like this in Black Ops, as quickly describing the location of an enemy can be difficult.
Feel free to add your own ideas to the Black Ops wishlist, remember we are only talking about the multiplayer game modes, not the campaign, or co-op modes.