Are any of them really "Difficult" to level?
Only difficulty come in making sure you have enough Water/Food to deal with the downtime.
I leveled my priest as Holy, at no point did i think it was hard, it was just slow.

Must be a slow topic week....

surely the question should be, which talent build is the hardest / slowest to level. a non BM hunter, non demon lock, or non shadow priest would have as much of a hard time levelling as a protection warrior, i suspect.

I have had experience with many classes, and it depends on the level range. When it got towards the longer levels 50+, I had the easiest time leveling my feral druid to be honest.

At low levels, there isn't much difference. Paladins are the worst. Go retribution and everyone mocks you. Go holy and take 3 hours to kill a critter.

a non demon lock would have a hard time? the utter lack of downtime for an affliction lock made my leveling incredibly fast

U forgot druids... i can level up a druid much faster than a mage. Fight in cat/bear form, go back on humanoid form and uve got ur mana regenerated, innervate if need. Also u can travel around fast with feral swiftness, travel form and flight form when u reach lvl 68. Druids have high survivability, we can stealth, got lots of HoT, and we can easly run.
(+its a funny class^^)
REROLL DRUID!

U forgot druids... i can level up a druid much faster than a mage. Fight in cat/bear form, go back on humanoid form and uve got ur mana regenerated, innervate if need. Also u can travel around fast with feral swiftness, travel form and flight form when u reach lvl 68. Druids have high survivability, we can stealth, got lots of HoT, and we can easly run.
(+its a funny class^^)
REROLL DRUID!

I've leveled warlock, hunter and shaman, and I must say that warlock was the easiest. Nothing to master really, go affliction, dot and wait. :) Enhancement shaman was easier then the hunter too. :/

Warlock->Shaman->Hunter IMO

Grajen is half right -- warlocks are easy to level, IF you know what you are doing, if you know how to play the class and use their strengths. If you don't understand warlocks they can be tough to level.

The problem with hunters is that they are too easy to level, even if you don't understand the class. Anyone can level a hunter to 70 (quickly, even), few can master them. But, again -- this is an old old topic and we all already know that right?

QFT.

TBH it's more like hunter > lock because hunters can use no mana and still own mobs. At least at low level locks will use a fair amount of mana and have to drink or eat at some point, hunters can 100% Ctrl+1, 1 every mob 10-70. shots just speed up the killing a bit

And thus we perpetuate the cycle

It takes awhile for rogues to get their most potent abilities. I didn't feel like a killing machine on my rogue until about level 30, same for my warrior. I found hunter absolutely boring unless I tried to take on multiple mobs at a time, but it does have very little downtime compared to my enhancement shaman.