I can't speak for the other classes, since I haven't played them yet. But Rangers really took a huge hit today.
All I intended to do today was knock out some Hunting quests before I go to work, because I'm creeping up on the levels where you start to lose side-quest tracking if you have too many open hunting quests. Imagine my surprise when I start with hunting quests for mobs that are 5+ levels below me so as to get them done as fast as possible, and the very first mob I attack barely took a scratch (granted I assumed that since they were low level garbage, I'd just phone it it). I start to pay attention to what I'm doing, and find that the damage reduction is so much that lower level garbage mobs are taking the amount of damage mobs at the same level as my Ranger should be taking.
After being disgusted at how long it took me to knock out just 2 hunting quests, and realizing I've got to leave soon to get to work, I figger'd I'd rant here first.
Now all day when I'm at work, I'm gonna be stewing in projected frustrations when I get back and attempt to work on current level content.