This is a current 3.3 list of what I personally consider the ultimate in itemization. This reflects my opinion and theory crafting and I really hope to hear some great feedback and gear choices that you guys are aiming for come Heroic content.
Thought I would add a quick link to Simcraft to this list if you are new to spriest this is very helpful. http://code.google.com/p/simulationcraft/
Here is a Stat List(ungemmed) for a set including all options listed individually and where there are more than one options:
Blood Queen's Crimson Choker
The Lady's Brittle Bracers
Plaguebringer's Stained Pants
Rep Ring and Rapid Ascent
Heroic Dislodged and Heroic Phylactery
"I've made a setup for our BiS gear, which is hitcapped if you are alliance and short by 6 hit if you are horde. For the gear where no socketboni are available I assumed 5sp for 1 socket, 7sp for 2 sockets and 9 sp for three sockets since that has been common on most pieces of gear."
Izolight http://shadowpriest.com/viewtopic.php?f=62&t=24912 (Give credit where credit is due) Obviously we both came up with the same list and since it was pointed out where the other was posted I will post his stats for the set since he accounted for gems and I added the haste for Heroic Phy from my list.
Crit: 1246 (38.65%)
Haste: 1167 (35.59%)
[Sanctified Crimson Acolyte Cowl]
[30 Sp / 20 Crit]
[Chaotic Skyflare Diamond]
[Blood Queen's Crimson Choker] (This is showing a yellow socket for me, perhaps wowhead's mistake?)
[Amulet of Silent Eulogy] (This is great for itemization and will keep you away from ANY hit gems)
[Sanctified Crimson Acolyte Mantle]
[24 Sp / 15 Crit]
[Frostbinder's Shredded Cape]
[Sanctified Crimson Acolyte Raiments]
Wrists: There are a few options here. Awkwardly Bejeweled are still scaling very high. I recommend with this full gear set up you move to one of the other options though. For this particular build you need the Brittle Bracers option to reach hit cap.
[Bejeweled Wizard's Bracers]
[Armbands of the Ashen Saint]
[The Lady's Brittle Bracers]
Gloves: These may appear less appealing than the Crit/Haste/Sp Gloves like Handwraps of Lifeless Touch but the method to this madness is simply to keep 4pc set while itemizing the best possible to reach hit cap.
[Sanctified Crimson Acolyte Handwraps]
[Crushing Coldwraith Belt]
Pants: If you are taking Queen's neck the hit pants listed below are a great option.
[Leggings of Woven Death]
[Plaguebringer's Stained Pants]
[50 Spellpower / 20 Spirit]
[Plague Scientist's Boots]
Rings: There is a hit one included if you are still working on that stat via itemization.
[Ashen Band of Endless Destruction]
[Valanar's Other Signet Ring]
[Ring of Rapid Ascent]
Trinkets: There are a few options here.
[Phylactery of the Nameless Lich] H
[Phylactery of the Nameless Lich]
[Dislodged Foreign Object] H
[Dislodged Foreign Object]
[Muradin's Spyglass] H
[Reign of the Unliving]
Main Hand: Frozen Bonespike is coming out on top but if you are having trouble meeting hit cap Barb of Tarasque reigns supreme.
[Barb of Tarasque]
[Shadow Silk Spindle]
GEM CHOICES: It is becoming ever popular to keep all socket bonuses in gear so I made a list of gems for which you may choose. A lot of priests consider it taboo to keep a 5 spell power socket bonus and I usually don't myself but I certainly can't make you change the way you gem.
[Intricate Eye of Zul]
[Quick King's Amber]
[Runed Cardinal Ruby]
Worshaka has a post here regarding Shadow DPS and has a Simcraft breakdown of stat weighing.
If you do the math on a few of these gear combinations(depending on what dropped for you) you will find out that there is 9 hit point deficit if you use Queen's neck and Crafted pants. Obviously you would not want to swap an entire item for 9 hit rating, this would not be optimal for any caster. It is therefore ideal to pick up one Ametrine to solve this. If you opt to go with Dying Light you will also run into a few hit discrepancies. This can be solved via [Deathfrost Boots], [Belt of Omission], or even [Snapper Extreme]. Also if you use the Amulet neck listed above you will be in the clear for hit.
I realize this is list Heroic content gear and is more literally a BIS list due to current item levels but do your best to get your hands on what you can. There are some really great items that are not on the list and if you come across them utilize them in your gear set as you see fit. I obviously do not have Lich King gear listed here because it is not readily available to me(unless you know something I don't) so it will be updated as I come across it.
If requested I will add some more easily attainable items for priests that raid a bit more casually. I just wanted to get a master list out to begin with.
Thanks for the read!