Attack power now scales with all of our abilities (or most anyways) at the same rate as spell power so yes we now use warrior gear. I recently switched from the Gavel of Unearthed Secrets to the King's Defender, dropped Seal of Righteousness for Vengeance and Retribution Aura for Devotion and have had no problems with threat.

In case you are wondering why the spell changes, Seal of Vengeance is applied to all 3 mobs you hit with Hammer of the Righteous and I switched Auras because I picked up Improved Devotion Aura.

Another reason Strength has become so important, and why Divine Strength was moved to the protection tree, is because it significantly affects your block value which will be very important when we get Shield of Righteousness.

Even with all this said, the plate gear still sucks in my opinion. Regardless of the changes, plate without defense or some avoidance stats just isn't tank gear to me. It appears more geared towards melee specs.