My long forgotten Troll Priest - Holybush has been collecting dust at a ripe level 38 for a while. Since I'm only raiding with my paladin, and my dear warlock is gathering dust, it's time to focuson a new alt.

Having all those extra left over badges and tokens Holy bush got a whole 3 pieces of heirloom loot for him. The PVE shoulders, the PVE robe as well as the PVP mace. While it is nice to have the gear, I've also tried to go shadow at level 40 after getting there with a Discipline spec. Well after I played with the shadow for a while I went right back to the discipline. Here is why:

Mana, mana mana. Mana regeneration is so fast with Discipline, just remember to put three points into the Spirit Tap and you almost never need to drink. With shadow I was doing a lot of damage but had to drink all the time.

You don't get hit. The bauble is amazing. You almost never get hit or take damage. As appose to shadow where you get beat up but regenerate all your life by end of the fight.

Holy Fire - I love this spell! This is my second favorite spell in the game after the shammy'schain heal. I love how now it has lower cast time and can be gliphed to go along with the smite.

Holy Shadow combo - This is a very strong point, you don't maximize either one but you have both available. Around level 40 there are tons of mobs who knock you and prevent you from casting in the same school of magic for like 6 seconds ( eternity). So having both schools available helps.

Well I think this is all I can think of. I'm going to keep leveling discipline for now and will see how well it goes.