Priest

Priest 5.4.1

Discipline
   This spec is currently lower on the healing charts but it does have its uses in raids, especially progression raids.

Stat Priority
Int > Spirit (Until manageable) > Haste > Crit > Mastery
375 Mastery = 1%
425 Haste = 1%
600 Crit = 1%

Haste
   Their are haste caps for renew however you are not speced into haste for the caps, you are speced into it for the faster heals and faster damage, i will explain the damage below in the rotations section. If you are interested however in haste caps even though you will not be aiming for them they can be found using the link below.
View haste caps here

Crit
   Crit will of course double damage and double heal, however it has a bonus that makes it useful, on a crit an absorption shield is placed on the target which absorbs which increase with mastery

Mastery
   Mastery will increase the size of your absorption shields, 375 points = 1%, and the size of your total heals by 1/2 that, 750 points = 1%, if your critical strike chance is say over 40% by default, mastery would be top stat for sure however that currently is not possible placing mastery at the bottom of the totem pole.

Talents
15 - Dominate Mind (Optional)
30 - Angelic Feather (Optional)
45 - Mindbender (Required)
60 - Angelic Bulwar (Optional)
75 - Twist of Fate (Recommended/Situational)
90 - Divine Star (Recommended/Situational)

The talents for a disc priest are mostly interchangeable, the only one that is required is 45 - mindbender, this provides the largest mana regen as of 5.4 (previously was solace and insanity). Divine star will give the biggest heal per mana cost if you can have good situations to use it, Cascade and Halo are to mana consuming to be useful and are only recommended during must use situations.

Glyphs
   Major
      Holy Fire (Recommended)
      Smite (Recommended)
      Purify (Recommended)
      Binding Heal (Recommended)
      Renew (Recommended)
   Minor
      All Optional

The glyphs are almost all crap unfortunately.

To be continued.....