I've come back from like a year and a half break and got my pally to 60 yesterday. Seems like general MTs have switched to warriors, should that be my priority instead? I pretty much play exclusively for end game raiding if that's necessary to know.
Just from what I've read on here and Reddit since I was researching the same thing between Paladin and Dark Knight...
The general trend now is all three tanks are viable, but in Savage Alex damage is at a premium. As such, some cutting edge groups are using Dark Knight as MT and Warrior as OT. Warrior damage is so awesome right now they are basically an extra DPS. Dark Knights do strong damage as MT and also have a cooldown that mitigates 30% magic damage which is great in the current end game raid. Paladins are being used as MT for the second floor since it's heavy physical damage, but they weren't the progression tank of choice.
Floor 1: DRK as MT, WAR as OT
Floor 2: PLD as MT, WAR as OT
Floor 3: DRK as MT, WAR as OT
Floor 4: I don't know
Now that damage classes have their weapon upgrades, I think it's not as important for the tank to push out as much damage, but it's something to consider. Warriors are definitely the "lock" for their OT ability and crazy damage, so you can't go wrong there. The other spot seems to change based on the fight.
Ultimately, you'll be fine playing whatever you prefer. I'm leveling both Paladin and Dark Knight for end game flexibility. I also prefer DRK for roulette and DF stuff, as well as farming. I imagine over geared groups might also want the higher damage tanks to speed stuff up. What I don't know is the trade off gained by letting your healers do more damage with a paladin mitigating more damage.
The next dungeon might be all physical damage again putting paladins back in the driver seat, so play what you like I say.