IF you are slow on the pick up (like myself), one instance. I picked Ramps (I don't do many raids).
1) Seals are awsome. The return (life/mana) is compareable (better if you ask me). A thing to note is an internal 4sec cd (can only proc once every 4 sec).
2) Judges are different but easy to get the hang of. They last 30sec and you get a proc chance of your choice (life/mana or can't run away). EVERYTIME you judge you do Holy Damage (no matter which one you choose). So as a tank you can use it for threat/damage and/or the proc.
3) Hammer of Righteousness*(HoR). You pretty much want to spam this. 3 targets for Holy Damg (causing threat).
4) Shield of Righteousness*(SoR). Yep, more holy damage.
5) Blessing of Sanctuary GO BLIZZ!!! The change on this is just awsome.
Quote:
Blessing of Sanctuary reduced to 1 rank, now reduces all damage taken by 3% and generates rage, mana or runic power when a parry/dodge/block occurs.
2% of max mana to be exact.
So, with these changes Prot Pallys have become much better MT's. I don't think that you will need to change your talents to move from being a off tank (mob tank) to a MT, just your spell rotation.
Now I've only played the PTR, so I haven't tried out any of the new WotLK instance or lands. That be said, with all the BC instances, you will rock. They have also added more of your spellpower (+spell damage) to all of your spells (my holy shield went from 128 to over 300). The only one I didn't really see as getting a big boost was Conceration.
With Blessing of Sanct and Seal of Light down time was next to nothing. The mana return from BoSanct is just awsome. Between that and a healer I almost never dropped below 40% mana (I also use Conceration maybe once or twice a pull... even in BC but in PTR 22% is a bit of your mana pool).
If you're ,OT or Mob Tanking (I call it this. It's when you have mulit mob pulls, basically the MT job you've been doing in BC instances), you'll use your seals, blessings, HS, and judges pertty much the same. Drop a Conceration if there is more than 3 mobs, and then spam your HoR till you have 2 mobs left. If your dps follows kill order you'll never lose agro. If you're boss tanking, you'll judge more, basically every time the cd is up (for the threat), and use SoR (as they both hit a single target for good Holy Damage), dropping the first Conceration and HoR.
Blizz has added Glyphs, one of those being Glyph of Avenger's Shiled. It cuts your targets to one but does 100% more damage (on your Avenger's Shield). Great if you are MT, sad if you are a mob tank. I don't think you can take it away and add it at will (the Glyph). I'm guessing if you take it away you'll have to make/buy a new one. So that is probally the big difference between a Prot Pally MT and OT.
*memory serving correctly, the range on these is melee range.
Learning curve? Not much. As I said it only took me one instance, and I picked ramps because it has a good mix if melee and caster mobs. Also, it's lower lvl so that if I messed up it didn't kill me :-)
GL