My title refers predominantly to Zombies. I am not a very casual gamer when it comes to Zombies. In Black Ops 1 and on the World at War maps I achieved very high levels and they took me hours to get to.
With Black Ops 2 Zombies, you literally have one thing to do; play Tranzit. Farm, Town and Bus Depot (the survival maps) are from the Tranzit game mode (effectively all the Zombies maps in one, connected by a bus route). Tranzit is immensely fun (especially with 3 other friends to frantically run around the bus with), but survival really, REALLY is not good enough. The maps are far too small (1-3 doors to open) and lack creativity. Supposedly their is going to be a DLC map for Zombies that will blow us away, but we'll have to wait and see. Nuketown is great (if you get the hardened edition or wait a month or so for it to be released as DLC), but not a lot of people have it.
Tranzit - 9/10 (if they added a few more modes of transport/ways to get around then easily 10/10).
Standalone survival maps - 4/10 (massive step back from Black Ops 1).
Bonus DLC map (Nuketown Zombies) - 8/10 (can't really be faulted, PaP machine and perks, but just not enough people have it yet to make it worthwhile to play).
Grief mode - 7/10 (Easy if you are good at Zombies, and can be annoying being put against very bad players as you win straight away).
Multiplayer has the same huge error as Black Ops 1; the hit detection and lag is un-playable. If they fix that (which is all they needed to fix from Black Ops 1), then it couldn't really be any better (except maybe making it harder for the endless amounts of children who play it to do well - prestige tokens, Hunter Drones and Lightning Strikes are too easy to obtain).
So Far (15 hours playtime multiplayer, 20 hours Zombies, and 2 hours campaign on Veteran):
Multiplayer - 7/10 (fix the lag and it's a 9.5).
Zombies - 7/10 (Tranzit and Nuketown save it from a 5).
Campaign - 8/10 (great graphics and feel, hopefully it has as good a storyline as Black Ops 1).