First, outside Prot, the redefined "Imp SoR" being expanded in function and accessible at the top of the holy tree is a direct buff to Tanks. A 15% boost to the two seals tanks use for threat generation is far from trivial, and synergizes well with the changes in the protection tree.
In protection itself, just looking at the new stuff:
"Touched by the Light" is huge. It's massive. 30% stam to spellpower breaks the Tankadin dependence on spellpower weapons and splitting item budget between actual tank stats and spellpower for threat. The healing buff is trivial, yes, and hardly worth taking for its own right, but the SP from Stam synergizes well with the stam talents in the tree and the damage multipliers now available to make gearing specifically for threat unnecessary. That's the big change we're seeing: we don't have to itemize around multiple mutually exclusive considerations to the degree that we did.
"Shield of the Templar", the revamped "Avenger's Shield", the new "Shield of the Righteous" spell, and "Shield of the Templar" synergize with "TbtL", "SotP", the stam talents, and "Hammer of the Righteous" (it's a weapon strike, no reason to believe it does NOT proc seals) to add up to massive threat generation (While "Guarded by the Light" shaves mana costs) without having to sacrifice Stam and Mitigation/avoidance stats. This isn't bloat: every one of these talents feed into the others, and they all feed into a gear scheme that leaves the Paladin free to stack tank stats to the exclusion of other considerations.