Priest

• 2 piece bonus - Your Flash Heal critical strikes cause the target to heal for 25% of the healed amount over 9 sec.
• 4 piece bonus - Your Circle of Healing and Penance spells have a 20% chance to cause your next Flash Heal cast within 6 sec to reset the cooldown on your Circle of Healing and Penance spells.

Paladin

• 2 piece bonus - While your Divine Illumination talent is active, your healing spells are increased by 35%.
• 4 piece bonus - Your Holy Shock spell causes the next Holy Light you cast within 10 sec to have 0.3 sec reduced cast time.

Cross-Realms Instances
We are working on a system to allow cross-realm grouping, yes, as we have regularly seen complaints in the past regarding players having a hard time finding a group for the dungeon they want to run. We have seen a lot of success with the cross-realm battlegrounds and want to apply that to dungeons as well. While the current LFG system works alright, it's not really intuitive so a lot of players just avoid using it all together.

We are still working on ironing out the details of this new system and plan to provide a more comprehensive breakdown on it in the future.

Most of the issues that players feel this will cause are things that are already happening to some degree and we will monitor the situation and make changes as needed. (Source)

Strange numbers in Tier 10 Set Bonuses on PTRs
Yes. It is much more work to create a spell in the first than to change numbers in it, so we often implement them in two steps: core functionality and number tweaking.

It may seem unpolished, but that's something you're going to encounter when dealing with betas, which is what a PTR build essentially is. Depending on when the data for the build gets pulled, we might be halfway through implementing something. The WoW team is far too large and churns out too much content for someone to go office to office to make sure everyone's stuff is 100% done and working before triggering a PTR build. We absolutely do that before making a retail build. (Source)

Trading Emblems of Conquest for Emblems of Triumph in 3.3
There are no plans to do this. As much as the triumph emblems will be easier to obtain in the next content patch, that doesn't meant we want to give players every triumph item by farming conquest emblems now.

Death Knight
Scourge Strike in 3.3
The Shadow damage will be less if the physical part strikes for less. We took that into consideration when coming up with the numbers. On the other hand, the Shadow damage will strike for more if you have all of the talents that prop up Shadow damage, and that part can crit separately.

From many reports it appears that the Scourge Strike on the PTR isn't working correctly, so most of what we are getting back right now are theorycrafted numbers, and some of those are wildly off. Let's get the ability working correctly and then the community can have another go at it. We're totally open to shifting some more damage from Shadow to physical. We're not open to titanic Scourge strike crits again, given that Unholy DKs already do so much damage from diseases and magic.

The goal is for it to beat out two Blood Strikes or Obliterate. (Source)