I think you are right... I am sure Treyarch had to "ramp up" the zombies on the old maps just for the simple fact you have black ops weapons in the toy boxes. I have definitely noticed more quadruple zombie swipings then before Rezurrection. It seems that
more an more zombies are like "Rocky". I red out much faster these days. Not too mention the weapons table in the box has been altered. You get the same guns but the randomness % has been adjusted. Not too mention the Ray Gun has been totally nerfed!!! You
get it alot now.. I have been in numerous 4 player games with 3 ray guns.. ridiculous.. thats how I know they are no longer the icons of destruction as before... theres absolutely no reason why Treyarch needs to tamper with Zombies.. who the hell has 30+ hours
to get to 99 legitimately anyways...its fun to play but way more frustrating than it needs to be...