adx,

Yes and no. A shadow priest (spriest) is a DPS spec; Holy is healing. They are different trees, they share some gear but some is different.

Really? It's not ridiculously obvious just by saying the words Holy and Shadow?

Holy= Healing

Shadow = Damage

I should have quantified what i was trying to state and i was asking more about the gear between the two. is there a difference in the gear that you have to collect per spec.

A Shadow Priest is DPS. A Holy Priest is healing.

With WotLK, warriors that spec Prot can also do decent DPS now. It's not uncommon for Warriors to be specced Prot while leveling.

I don't know if the same applies to Priests or not. Can a Shadow Priest heal 5-mans and 10-mans?

Gear differences between shadow and holy/discipline priests is pretty small.

It's sort of the difference you'll see in gear with a holy priest vs a mage. The mage (or on this case the shadow priest) will probably be a little more Crit focused and probably have less Spirit. Holy priest gear will have less crit and more Mana Per 5 and spirit.

As to a shadow priest healing instances, it CAN be done but it's very rough. The talent focus is sort of required since healing didn't received a buff when dps did with the last major patch before WotLK.
If you're going to ask a shadow priest to heal you better have a very good tank with high hp/defense (to smooth things out) and minimal mobs that have no agg table or randomly throw damage on players.

Sort of like having an arms warrior tank, it's not TOO bad but you can tell and it makes things harder.

A shadow priest "can" heal 5 mans regular dungeon. The only problem is mana regen. Shadow spec is not returning any mana while healing. They also have to drink. A lot. Now granted, it depends on the tank and how much group damage, but a shadow can heal, but I would not recommend it.

The gear does tend to blur together. Spirit is definitely useful to healer, and shadow can take advantage of it to a point. The same goes for crit rating. About the only real difference is hit rating. Healers do not need hit rating (at least in pve), because they (generally) are never dps'ing the mob/boss.

In a pinch we can (I'm shadow), but it's as it's off-spec the party getting healed needs to be pretty damn well geared to not insta-die.

Holy vs Shadow Gear differential.

In my opinion (as a shadow priest)
Shadow Priests stack Spellpower, spirit, mp5, crit, haste
Holy priests stack Spellpower, MP5, Spirit, Haste, Crit (with the last three being based on taste)

As a shadow priest, crit is 'cool' now that our bread and butter can Crit, but MP5 and Spirit are much more important now that they have gimped our mana recovery ability (Vamperic Touch requires Mind blast to trigger, and returns LESS MANA than the two spells combined cost).

For Holy, Haste is nice to get off your big spells, but much of your healing (esp in 5 Mans) will be PW: Sheild and Renew (instants) and flash heal (which is fast already).

And it goes without saying, that stacking +hit as a raiding SPriest is important but completely useless for Holy Priests.

Just my 2 coppers worth.

@Candina. Sorry, but some of what you posted on holy priests is incorrect. Spirit is much more important than mp5, it's our primay stat as it gives us regen, mp5 and spellpower.

You also say that haste isn't important (in 5 mans) as you'll be using pw:shield,renew and flash heal more often than not. I agree that haste isn't that important until you're raiding, at which point you can get your holy priest advice somewhere other than wowinsider comments, but greater heal, flash heal and prayer of mending are much more important to a holy priest than pw:s and renew. They're useful, but far from our primary spells.

Shadow (DPS) needs Hit on gear. Holy (Healing) does not, at all, not even a little bit. NO HIT EVER... Unless you plan to lolsmite, leave the hit cloth gear to the SPriests, 'Locks, and Mages.

/sigh

"Holy (Healing) does not, at all, not even a little bit. NO HIT EVER..."

This is a lie. It sounds like it ought to be true, but it is not.

ALL priest crowd control depends on spell hit. +hit on gear is the difference between Mind Control succeeding and allowing your group the buff that the mob can give vs. Mind Control failing and pulling the entire group of mobs onto the priest; it's the difference between Shackle Undead successfully crowd-controlling an undead mob vs. Shackle Undead failing and letting that mob get to the tank's AOE damage (in the *best* case scenario). And all of the priest's crowd control has a heartbeat resist, where +hit reduces the mob's chance to resist.

This is not to say that Holy priests should stack +hit. They should take Spirit, Intellect, Haste, Crit, and Stamina before they take +hit gear. But it's a lie to say that they don't need it at all.