There's not really anything that can be done. You could be on a server that has people from Canada, Australia, and Russia all in the same match.
On top of that, you have people on a wireless connection or less than a 3mb connection that are causing the lag comp to go through the roof.
I spent a couple of hours last night going throught all the game files and i think i found a solution for the lag compensation that would most likely work for all of you guys who experience the lag of lag ompensation. Here's what you have to do:
1. Turn off Your PC and leave it off.
2. Check your funds and go to a shop that sells consoles (if you alreade own a console skip this step)
3. Spend on the console (xbox360) whatever it costs)
4. Equip yourself with Black Ops 2 For Xbox360
5. Go back home and connect the conole to your TV.
6. Get Black Ops 2 started on your console
7. Deal with the fact that from now on you have to play the game using a f*****g game pad plus aim assist!!!???
8. Enjoy the game with no/much less lag/lag compensation
I hope I helped everyone solve the lag related problems.
But seriousy now... there's nothing you can do mate. Unfortunately you will have to learn to live with the lag