Grogin of Area 52 wanted to know how viable levelling from 60-70 in Outlands as a Protection Paladin is.
Short answer, it's very viable. I levelled from 60 to 70 as Protection. Of course, I level by questing, and very rarely grind for experience, so I don't know any specific spots which are good for AoE grinding while levelling. Once you hit 70, though, you have to go to the Demon Hunter training grounds at the Temple of Karabor in Shadowmoon Valley. It is the Protection Paladin version of Paradise.
However, there are a couple of things to watch out for. There's not a lot of true Protection gear until you hit 70 and Netherstorm. Most paladin quest rewards tend to be str/int/sta/spell damage. Luckily, most quests don't make you choose between warrior tanking gear and paladin gear. So you can use warrior tank quest rewards for your tanking set, and paladin gear for general levelling if you prefer.
Personally, I recommend levelling as Protection/Holy rather than the standard tank build of Protection/Retribution. I find Spiritual Focus invaluable while soloing, especially when undergeared. Also, take Reckoning. It's very good while levelling, especially for regenning mana with Seal/Judgement of Wisdom, though most tanks spec out of it when they hit raid content.
The only other thing about levelling as Prot that I can remember is that you get Seal of Blood/Vengeance at level 64. Try them out and see if you like them better than Righteousness. I tried Vengeance for a bit, decided it was silly, and went back to Righteousness. Vengeance can give more damage, but half the time it falls off. Righteousness is always reliable.
If you're bored, you can "twist" Vengeance and Righteousness. Cast SoV, after 10s Judge it, and then switch to SoR. You'll get SoR damage while the Vengeance debuff continues to tick. It's decent extra damage for the last part of the fight.
Anyways, as long as you save the warrior tank quest rewards, you should also be able to tank any of the instances as you level.
Hope that helps!