I don't like any of the Black Ops II zombies maps enough to deem one a favourite, but the ones I play the most are Nuketown and Farm. Although Nuketown is small and cramped, it feels a little more like Black Ops I Zombies than any of the other maps so far (in my personal opinion). And Farm has a lot less lava and in turn less burning zombies which I find very annoying in Town as it's caused me to go down on a few occasions when I've been training zombies or some explode too close.
The two maps I play the least would be Bus Depot and Die Rise. Die Rise particularly is a bit of a hassle due to having to wait for the elevators to get your perks and there's no real decent place to train zombies except on the roof (again, my personal opinion).
In my personal opinion my favorite zombies maps are all of the original WAW maps. Purely because it focuses on the main purpose and objective of zombies, and that was to see who could get to the farthest round amongst all of your friends. Its what started it all, and turned zombies into what it is today. Further more I havent found a map that is absolutely horrible, and I've noticed that most of the complaints about many maps were based simply off of how people play the map. Often times the majority of complaints were because the map's layout didnt cater to their specific style of play, or it was because the people they played with took advantage of certain aspect of the game that makes the game less fun for other players. Which even in that case isnt the map's design flaw its based solely on the players being rude to others. All in all I love Zombies and dont see anything wrong with it.
Mine would be TranZit. Said no man ever? jk To me its Buried. Tranzit is the worst
Worst= Tranzit not much to do. Everything is so complicated and takes a long time to do which takes away from the main objective which is killing zombies. Basically having to leave one zombie alive and go put the turbine and go into the power place put down the turbine and run like hell before it runs out and disappears and go into the pack a punch room which you also have to build. Takes about 7 minutes.
Best=Mob Of The Dead or Origins both maps are pretty fun and have challenges in them.
Worst Ever = Diner. Concept wore thin after 2 minutes.
Hated Tranzit when the game was first released but in the recent months have returned to it and it is not as bad. Team must stick together though.
Best: MoTD. I enjoyed doing the challenges on this map far more than the others.
Good maps when I just want to slay endless Zombies and not have to work on challenges: Town and Farm. Town mostly coz of the PaP machine.
Best BO2 maps
Honorable Mention Farm
Best: Mob of the Dead
Honorable Mention: Nuketown, Origins