As you are your first steps into The Sunwell Plateau you might also be wondering what gear has the highest potential for a holy priest. In this guide I won't be including items you can get from different professions OR badges, only gear that is available from Black Temple and Hyjal Summit.

First of all, all holy priests differ from one another. Some gem for mana regeneration, others go for pure healing and some of them go for something in between. It's really hard writing a guide that includes all of those aspects so I'm writing it from my point of view and what I think is the best choice for holy priests in general, which is the more balanced type of gear.

 

I assume most of the holy priests at this stage are Circle of Healing specced, or at least should be. Yes, spirit is a really nice raid buff, but you're pretty useless as a healer seeing there are paladins providing blessings, also taking care of the single target healing.

Talents

I suggest going for: www.wowhead.com/?talent=bxRhzhxZfVx0fzqVhVo
In the holy tree, I picked Spell Warding over Inspiration to max out my own survivability. Most endgame boss encounters have a lot of magical raid damage going on and this is a nice way to reduce incoming damage and boost my survivability. Seeing I am on raid healing more than on maintank healing (where Inspiration could be nice) the 10% less spell damage taken is worth more than the Inspiration talent in the long run.
 

So, what gear should you pick and how should you gem the different pieces? Remember this is from my own point of view, according to my own taste, there is really no right or wrong here

 

Headpiece: [Cowl of Absolution] (Archimonde, Hyjal Summit)
Necklace: [Brooch of Nature's Mercy] (Akil'zon, Zul'Aman)
Shoulders: [Mantle of Absolution] (Mother Shahraz, Black Temple)
Cloak: [Shroud of Forgiveness] (Gurtogg Bloodboil, Black Temple)
Chest: [Vestments of Absolution] (Illidan Stormrage, Black Temple)
Bracers: [Bracers of Martyrdom] (Rage Winterchill, Hyjal Summit)
Gloves: [Gloves of Absolution] (Azgalor, Hyjal Summit)
Belt: [Belt of Divine Guidance] (Illidari Council, Black Temple)
Legs: [Leggings of Eternity] (Archimonde, Hyjal Summit)
Boots: [Boots of the Divine Light] (Trash drop, Hyjal Summit)
Ring 1: [Band of the Eternal Restorer] (Scale of the Sands reputation reward) / [Blessed Band of Karabor] (trash drop, Black Temple)
Ring 2: [Blessed Band of Karabor] (trash drop, Black Temple)
Trinket 1: [Earring of Soulful Meditation] (The Lurker Below, Serpentshrine Cavern)
Trinket 2: [Memento of Tyrande] (Illidan Stormrage, Black Temple) OR if you are an Alchemist, the [Redeemer's Alchemist Stone] is just as good.
Main hand: [Crystal Spire of Karabor] (Illidan Stormrage, Black Temple)
Offhand: [Scepter of Purification] (Archimonde, Hyjal Summit)
Wand: [Naaru-Blessed Life Rod] (Reliquary of Souls, Black Temple)

A good choice instead of Crystal Spire + Scepter would be [Staff of Immaculate Recovery] from Gurtogg Bloodboil.
 
Gems

Since the change they made to spirit/intellect and its effect on mana regeneration, spirit has become the best stat you can stack up on for mana regeneration as a holy priest. Therefore the most balanced choice of gem would be Purified Shadowsong Amethyst in all blue and red sockets and Quick Lionseye in the yellow sockets. You will start noticing that spell haste is worth a lot when you have to make up for the insane raid damage going on in Sunwell Plateau so stacking it to a certain point is definitely worth it as it also affects your global cooldown (win for the CoH spam). If you dislike haste, a good choice is the Luminous Pyrestone for the yellow sockets.
The absolute best choice for the meta gem is the Insightful Earthstorm Diamond. You'll easily reach the meta gem requirements with the abovementioned gem choices.
 
Enchants

Bracers and gloves: for this I pick +healing, it being the most viable enchant.
Chest: +6 stats is the best choice. I prefer using this enchant over the 6mp5/15spirit enchant due to the fact that you gain more from 6 stamina, 6 intellect and 6 spirit which makes it a more balanced choice.
Cloak: there aren't many good cloak enchants, therefore the 15 shadow resistance on cloak would be the best choice. There are a lot of shadow spells, on bosses and on trash, that can be resisted and reducing every bit of incoming damage means increased survivability.
Boots: Boar's Speed would be the best enchant for the extra run speed (shines on Felmyst for example) and stamina. Forget about Vitality.
Weapon: the obvious choice is +81 healing.

With the above gear gemmed and enchanted, assuming you're not an enchanter (for the rings) and with the earlier mentioned spec you will have the following stats:
8431 HP / 10305 mana / 637 mp5 (247 while casting) / 2342 +healing / 5.9% haste.
 
This setup for me is an excellent balance between mana regeneration, stats (HP is not to be underestimated) and healing power.

 

 

Headpiece: Cowl of Light's Purity  (Kil'jaeden, Sunwell Plateau)
Necklace: Brooch of the Highborne  (Felmyst, Sunwell Plateau)
Shoulders: Shawl of Wonderment  (Eredar Twins, Sunwell Plateau)
Cloak: Shroud of Redeemed Souls  (Eredar Twins, Sunwell Plateau)
Chest: Robes of Faltered Light  (Mu'ru, Sunwell Plateau)
Bracers: Cuffs of Absolution  (Kalecgos, Sunwell Plateau)
Gloves: Handguards of the Dawn  (Kil'jaeden, Sunwell Plateau)
Belt: Belt of Absolution  (Brutallus, Sunwell Plateau)
Legs: Breeches of Absolution  (Illidari Council, Black Temple)
Boots: Boots of Absolution  (Felmyst, Sunwell Plateau)
Ring 1: Ring of Flowing Life  (Bind on Equip ring crafted by Jewelcrafters)
Ring 2: Blessed Band of Karabor  (trash drop, Black Temple)
Trinket 1: Glimmering Naaru Sliver  (M'uru, Sunwell Plateau) / Earring of Soulful Meditation
Trinket 2: Memento of Tyrande  (Illidan Stormrage, Black Temple) OR if you are an Alchemist, the Redeemer's Alchemist Stone is just as good.
Mainhand: Golden Staff of the Sin'dorei  (Kil'jaeden, Sunwell Plateau)
Offhand: -
Wand: Wand of Cleansing Light  (trash drop, Sunwell Plateau)

 

This gear is based a lot on haste. For less haste and more mana regeneration I would probably change both the rings into 2x Ring of Harmonic Beauty (trash drop, Sunwell Plateau) for a nice boost in spirit.

However, with the gear abovementioned, gemmed after my choice, you will have the following stats:
8471 HP / 10905 mana / 714 mp5 (274 while casting) / 2527 +healing / 20.37% haste

 

 

 

Since this is a guide written from my own perspective, some other priests might not agree on the gear or gems I chose. However, remember that gemming and picking gear as a holy priest depends on your play style. The only thing you should always keep in mind though is that you must not ignore any stat.
Sure, 2800 healing might look good on paper and your character sheet, but you won't last long in an intense fight. Your heals might land for 300 more, but with more mana regeneration your total healing output will be higher in the long run.

The key is to maintain a balance, maybe you had a shadowpriest/shaman last week but next week you might be in the MT group. Try to find a balance with gems/enchants while keeping in mind that you could always end up in the worst possible group so it's good to know that you can last in any situation.

Another hot tip on consumables is to use Elixir of Draenic Wisdom + Elixir of Mastery, Brilliant Mana Oil combined with 44 healing / 20 spirit or 20/30 stamina / 20 spirit food.
 I'm fine with around 2500+ healing and with that capped I usually stack other important stats instead.
 
Good luck in Sunwell Plateau and don't forget to top the healing meters while staying alive (and stay away from the NumLock key while buffing up on the Eredar Twins).