A couple of other changes have been datamined from the latest PTR build by MMO-Champ :-
1) Lay of Hands can no longer be cast on yourself.
2) Aura Mastery now lasts 6 seconds, down from 10.
Additionally, the Sacred Shield change is in the tooltip for this build. AM is a PvP nerf, LoH is no longer a Paladin Tank cooldown. But really, why was this necessary, LoH has been like that since Vanilla.
Oh wait, I know why, it's the 7800 mana it grants in PvE combined with the Glyph of Divinity. Why not just change the Glyph to 'has no effect when LoH is cast on yourself'?
Here's another possibility: is this a nerf targeted specifically out our performance in Battlegrounds? After all, rated BG's are coming soon and there may be a fear that Paladins will dominate this new 'PvP bracket'.
Patch 3.3's latest build includes the following change:
Sacred Shield: The damage absorption effect from this ability now triggers only once every 30 seconds. [As opposed to once every 6 seconds]
Infusion of Light: This talent now also reduces the cooldown on the effect of Sacred Shield by 12/24 seconds.(Source)
Sacred Shield's baseline effect just got hit to be 20% of it's current effectiveness, which represents a huge nerf to the value of the skill for any Paladin not deep in Holy. To put it into context, a baseline Sacred Shield in 3.2 will proc up to five damage shields over 30 seconds with one cast, a Patch 3.3 SS will proc one.
Why? What's the motivation? Well, the bugbear of many a Paladin over the last few years has struck again: skill nerfs because of PvP. Prot-Holy build is still very popular as a spec and deep-Holy often gets a lot of criticism for being non-interesting for a PvPing Paladin compared to the control and offensive potential of Prot-Holy. Prot's big issue was one of mobility without Holy Shock, and so a strong Sacred Shield remains powerful against teams without an offensive dispel. By making Infusion of Light required for a PvP-viable Sacred Shield any skills deeper than 24pts in Prot - including Ardent Defender, Avenger's Shield, Touched by the Light and Judgments of the Just - are immediately taken off the table. I'm not qualified enough to judge if a crippled Sacred Shield will in fact cripple Prot-Holy but if I had to guess I'd say it's not good for that gameplay niche, to put it mildly.
As a side-effect Ret will obviously take a huge durability and utility hit in PvP as even without Divine Guardian the ability absorbed a non-trivial amount of incoming damage, the Shield will absorb less damage than an instant FoL will heal. Finally, Sacred Shield becomes a very weak ability for Prot damage mitigation in any Raid with no Holy Pally.
Is Sacred Shield now a worthy lvl80 baseline ability for all specs? For any specs? God no.