Here are some changes to keep in mind:
- Judgment - You no longer need to judge. It does not return mana or give haste anymore. You can pretty much drop this button.
- No More Auras - The auras have been removed. Aura Mastery has been renamed Devotion Aura, but works as a damage reduction cooldown. Crusader Aura has become a paladin-only passive. The Seals now occupy the same UI space.
- Store Up to 5 Holy Power - You can store up to five Holy Power, though you can still only spend a maximum of three. So you can effectively bank two Holy Power for emergencies.
- Intellect Does Not Give Mana - Intellect no longer increases your mana pool. Your mana pool will be fixed in size at max level for the full expansion. This makes Intellect slightly less valuable (though still very valuable because it gives you spell power), and Spirit more valuable.
- Holy Radiance - Holy Radiance works slightly differently. There is no HoT, and the target gets twice as much healing as the other people. You still want to cast it on different targets in succession, but it won't be wasted if you cast it on the same target twice in a row.
- Light of Dawn - Light of Dawn is not a targeted cone anymore. Instead it's an AoE all around the paladin.
- Denounce - Apparently we get a spammable nuke in Denounce. Probably is our primary damage spell for soloing.
- Talent Trees - The old talent trees are gone. Pretty much all the important abilities have been rolled into the base Holy Paladin, and we have new abilities in the new Talent structure. I'll look at the talent tree in a future post.
- Glyphs - Prime glyphs are gone, only major and minor glyphs remain. Vital Prime glyphs (such as Seal of Insight) have been rolled into the base spell.
I think that's about it. Not needing to Judge is the biggest change in playstyle, but the new Talents will give new abilities to replace Judgement. Otherwise it's pretty much the same as in Cataclysm.