This might seem like a better variant on the tri-healer team. In this case druid cyclones and removes an opposition to turn it into a 5v4. I'm still not convinced though that the resto shaman is a good choice since all the healing in this party has a casting timer.

I don't disagree, and that to me seems like the major flaw of shamans, lack of survivablity, not lack of CC or anti-CC.

In practice though, what then is difference between an MS warrior and an Enhancement shaman for ease of training? Plate without a shield isn't that much more mitigation than mail. Other than intimidating shout, what prevents warriors from getting trained down just as fast?

Fear, seduce and sheep come to mind as being the most important reasons to have defensive dispelling.

In practice, warriors have far more useful debuffs than enhancement shamans and bring more to the table offensively. Mortal strike, hamstring, shouts, etc. Shaman totems are nice, but a shaman of any spec can provide the same (and most enhancement shamans don't spec into totem buffing talents unless they are raiding). Enhancement shamans have only stormstrike and shocks as semi-debuffs, and NO STUN (this hurts a lot). Rogues have a variety of debuffs as well as stun, superior burst damage that is activated rather than procced. Windfury procs are rather undependable in PvP, and you need to be able to damage "on demand" when a target is chosen. They cannot get out of snares/slows like rogues/warriors can (sprint/charge), and they have no dispel methods for magical debuffs.

This should tell you how useful enhancement shamans are in PvP: with 15 points in restoration I was healing the elemental shaman in BGs rather than trying to melee.

Hitpoints as well, and the fact that assist training a warrior that is getting spamhealed is by far the fastest way to lose, as he'll spam HS MS WW to no end.

true, but with PVP trinkets and whatnot it's still not as important as it used to be

I'd love to see priests get an instant cast disease debuff so that dispel disease is actually worth ANYTHING in PvP. Or give us the ability to dispel poisons like paladins can. -.- But I digress.

I find it odd that no one has mentioned how mages/warlocks seem to be sidelined by physical DDs in arenas. Can a team composed of 2-3 healers and magic DDs fare well against an onslaught of physical damage?

Shamans also have, potentially, the best spell cast prevention spell. Earth Shock is ranged, has a short cooldown (5s with Reverberation talent) when compared to Counterspell, Silence, and Spell Lock, and has a 20 yard range. Rogues may be able to stop more consecutive spell casts, but Shamans have the benefit of doing this from range and adding damage on top of that (whereas a Rogue using Kick wastes potential damage from the Energy spent). The only thing a Shaman forfeits when interrupting a spell is global cooldown. If mana is a factor, rank 1 ES can be used as well.

Edit- But I'm also very interested in hearing how Elemental Shaman are faring in both raid and PvP settings. I'm going to be rolling one soon and it's been about two years since I played a Shaman (I was 23 Elem, 7 Enh, 21 Resto) and I'll most definitely be using an Elemental / Restoration build, but I'm unsure which tree I want to focus primarily on.

Dispel Poison and Dispel Disease don't remove Entrapment, Polymorph, or Freezing Trap.

And I'm quite aware that totems are easily killable once you target them - the issue is spending the time to target them and the attack timer to kill them. In the arena, time is your most valuable resource. If I spend my time hitting totems, I'm not hitting my opponents. I have a /tar (list of totems) /petattack macro that i mash against teams with totems, because I can't afford to spend time killing them myself.

As for the other post saying defensive dispels are less important because of UA and shadow priest debuffs - Shadow Priests and UA warlocks are two of the most outright vulnerable classes in 5v5. I have yet to see an effective team that uses either. Competant assist trains almost immediately hit warlocks, and if they're not soul link, they pretty much just die.

Not to mention the fact that "topping off" with UA is pointless, because the dispel order is random.

In the testing I've done, the first and last buffs are the most sticky, but the order of removal is random.

I agree completely with the comments on the undesirable role of Enhancement shaman in PvP.

However, not much has been said about warlocks, apart from Elendril's post. I would be curious what roles people have found them to be strong in, and what roles to be weak in. I only have a week's experience in 5v5 so far, and improved Howl of Terror has been amazing. Beyond that, I'm still struggling to find what is best the class can bring to the table.

The main problem with Elemental Shamans is that their burst is ridiculously easy to predict. Mind you, this might be because my guild has traditionally been full of 33/0/18 Shamans for years, but they typically blow their load within the first 30 seconds. Elemental Shamans (or Shamans in general) are really easy to lock down. For example, one rogue will easily keep an Elemental Shaman occupied for an indefinite amount of time.

It's just important for whoever is being assisted on to pay attention to where the Ele Shaman is at all times, in order to LOS his nukes if possible. Otherwise, assigning someone to screw around with them the whole time can easily throw off the Shaman's assisting.

An Enhancement Shaman definitely does not belong in 5v5. A melee class without a Mortal Strike debuff or significant locking down ability seems like dead weight to me, unless the Enhancement Shaman is ridiculously good (I've never seen one). I feel the same way towards Ret Paladins.

As for Resto Shamans, well, Overrated used to run a group with a Resto Shaman and no Paladin and hey, they're doing pretty well now.

We ran into a Destruction specced Warlock that we handled improperly for the first few games, then we figured them out and regained the points we lost from losing and then some. Basically he had tons of stamina, would run around trying to get the melee assist train on him and would assist on their main target with backlashed shadowbolts and shadowburns. So when I switched off him and we just left the Warrior on him he basically did nothing the whole game.

This whole discussion should be focused on Arena, and particularly 5v5, since that is the bracket that matters. It is worth challenging assumptions learned in BG, world PvP and dueling. This isn't AV.

Don't attack the warrior has long been a 'fact' of PvP. But why is that? Here are some theories to why.
1. Attacking them gives them rage which allows them to make full use of their attacks. If you leave them alone they are less dangerous.
2. Attacking them gives them enrage, again, more dangerous.
3. Backed up by heals, they are hard to kill. (This is the assumption I'm challenging here)
4. They can be 'safely' ignored, since they just aren't that dangerous. (If this were true it would be a reason not to bring them at all)

Again, in practice, how many more hitpoints do warriors have then similarly geared shaman? Compare the Gladiator itemization for:

* Warriors - http://www.wowhead.com/?itemset=567
* Enhancement Shaman - http://www.wowhead.com/?itemset=578

Total difference
* Warriors: +2511 armor, +9 stamina, -1 resilience, +2 Str, -1 crit

Armor is only relevant if the damage is physical. So other than more armor and intimidating shout, how are enh shaman any harder to kill than a 2H warrior?

Balance Question/Speculation
As a side note, assuming Enh shaman are too weak in PvP to be viable, what would getting a version of rogues 'Quick Recovery' do for balance? Basically, increase the effect of all heals (only on themselves) by 20% or so? This would certainly make them much more survivable, but is it too much/not enough?