I'm not saying that the PVP wasn't fun in KO but after learning how to PVP in WoW myself I can honestly say WoW requires 100 times more skill if you want to use your class to it's fullest.
Let's compare some classes, shall we?
Statwise you just stack hp and str. In PVP you can beat pretty much anyone just by spamming one skill (depending on your gear of course) and you need absolutely no skill to spam that one button.
Q: What about comboing, it requires skill?
A: Have you ever watched those babashoppers play? Almost all the servers are full of them and none of them can play properly, yet they pretty much rape you without any kind of effort
Depending on what kind of PVP you're about to do you need to stack following stats
Fury: Armor penetration, crit, str (ap) and stamina. Fury is not really a good spec for PVP, unless they make some changes in the talents. It's good in PVE gear for ganking people in battlegrounds but that's about it, you'd need way too many talents from other talent trees to make it effective in the arena so it's not worth it.
Arms: Armor penetration, str (ap), stamina, crit. A really good spec for PVP, an arms warrior that knows what to do is pretty much impossible to kill unless you happen to be a death knight.
Protection: Armor penetration, block, defense rating, stamina, str (ap), crit OR Armor penetration, crit, str (ap), stamina. Protection is not that known for PVP but currently it's probably the best spec for warrior PVP wise. It does require some gear but once you have that gear you're unstopable. Playing protection also requires alot of skill.
Minor and/or hp pot spam, 10(?)ish skills that are useful for PVP.
After the minor nerf rogues became a bit more balanced class (there are still tbl editors who get rid of the minor cooldown). So basically you run stealthed and spike everyone who looks bad geared, then run away or you try kill stealing.
Obviously not everyone plays like that but it's pretty common nowadays. Rogues require the most skill to play if you want to make NP instead of losing it. It is rare to see a rogue with a good minor combo because it requires good co-operation with your both hands and eyes. (No I'm not talking about jacking off, you perverts)
Basically you just stack dexterity and nothing else, of course you get hp from uniques and that also gives you more mana.
I won't bother typing too much about the different specs because I haven't played a rogue for too long so obviously I can't possibly know everything about it. But lets get this started atleast.
There are 3 specs for PVP, obviously just like every other class. The most common on is mutilate spec which highly relies on keeping your enemy stunned. Personally I love this spec because it's really simple, even for a noobie like me. But! Even the "easiest" spec for rogue requires alot of skill if you want to be do decently well on the arena. By using their cooldowns a good rogue can easily fight against 3 opponents (depending on the class of course.. damn paladins..) and probably kill them all. Since rogues are using energy you can't just spam one skill and hope to kill someone, it just doesn't work. You need to be calm and keep an eye on your energy while you're stunlocking your enemy.
In battlegrounds rogues are really annoying because they, just like in KO, can use stealth and just choose their opponents.
As for stats you stack Armor penetration (optional), Attack power (agility), stamina and crit.
Crap, I'll finish this later.. gotta go to work, I'll just post this reply so you guys can QQ how wrong I am. Obviously for pvp resilence is needed but I didn't bother including it there, yet atleast.
Okay I'm feeling really lazy so I'm not sure if I'll bother comparing priests and mages.
I guess what I'm trying to say here is, in WoW you have to take in account so many different things unlike in KO where stacking one or two specific stats is enough.
What makes WoW so much better (for me atleast) are the talent trees that allows you to tweak your character to fit your playstyle. Also the class balance is being monitored all the time and there are changes in every patch if not pvp, atleast pve-wise. Oh yea and I almost totally forgot, you only have 4 classes to choose from in KO but in WoW you have 10 classes so there's something for everyone.
I'm not saying that I'm totally right because people have right to have their own opinions but personally instead of grinding 200+ days of exp to hit lvl 83 in KO I'd prefer spending 2 weeks to hit lvl 80 in WoW. The PVP is really alive and depending on the battlegroup you can keep doing it 24/7 if you want to. What I've heared KO's pvp is almost totally dead on old servers unless it's CSW or Lunar Wars, even then you're most likely facing fully babashopped characters.
I won't even bother mentioning PVE because KO doesn't really have one.
My bottomline is, you need to be alot more skilled in order to be a successful player in WoW than you need to be in KO.
I also should've been more specific about the whole thing but there's way too many things to mention so I'm just keeping it fairly simple.
I guess I should add some videos to prove my point.
Mage pvp: http://warcraftmovies.com/movieview.php?id=39506 <- Vurtne, one of the most legendary mages in game. The video was relased 3 years ago but it's still one of the best and funniest mage videos out there.
Priest pvp: http://warcraftmovies.com/movieview.php?id=133081 <- Hydra, probably world's best priest at the moment. Unlike in KO, priests in WoW are either healers or casters.
Warrior pvp: http://warcraftmovies.com/movieview.php?id=121203 <- Gforce, one of the best warriors out there, he's mostly playing arms specced.
Some machinimas worth watching:
http://warcraftmovies.com/movieview.php?id=53953 <- Tales of the Past 3
http://warcraftmovies.com/movieview.php?id=97157 <- The Craft of War