By now there has been so much buzz generated about dual speccing for character that blizzard will be hard-pressed to implement the feature at some point in the future or at the very least come up with one hell of a good reason why they don't.
I for one see a lot of potential problems with dual specs but despire being on the fence about the whole mechanic there's really no point in dwelling on the greatness or doom and gloom that is projected to come with dual specs.
For better or for worse we will most likely be looking at a dual spec system in the near future. So the question begs to be asked which characters will benefit the most from dual-speccing and what will those characters have to put up with as a result of actually being dual spec.
I am only going to briefly cut into what possible spec combinations could be and what pvp,pve impact that may have in favor of predicting the winners and losers of the dual spec in my humble opinion. I am also assuming that all trees are viable even if some classes clearly still have significant problems with one or more of their talent trees.
So from worst to best we start off with:
#10 The Rogue
Dual speccing will give the rogue the awesome ability to spec into not one but 2 dps trees. While we can certainly opt to have a PVP spec and a PVE spec in the end we're damage dealers and there's very few situations that require the ability to be able to switch from a pve mode to a pvp mode on the fly.
The rogue's utility is barely increased by having 2 specs available to them and the different itemization between a pvp and a non-pvp spec means the rogue would be dragging 2 sets of gear around at all times or if not would make his off-spec redundant. I can't think of any situation where having the choice between combat, assassination and subtlety could be considered crucial and as a result most rogues will get very little benefit from the ability to dual spec.
Beyond saving some gold on respeccing on a regular basis the rogue gets nothing out of the dual spec scenario and is well and truly hosed.
#9 The Mage
On position 9 we find the mighty mage. Another DPS class that will have the potential to spec into 2 different DPS trees but unlike the rogue's talent trees the mage's talent trees are very distinctly different from each other in functionality. Combining fire and frost (no not frostfire...) will allow the mage to switch between pure DPS and very controlled DPS. With arcane being the new PVP spec the mage can now choose between dual speccing into a solid raid dual spec with fire/frost or a raid/pvp combination as arc/fire or a pvp control spec as arc/frost.
All this nonwithstanding the mage is still a pure DPS class and the increased utility that comes from being able to switch between frost and fire for example will be more useful in a solo setting than in a raid setting where things are already more controlled.
#8 The Warlock
We continue with the pure DPS classes and run into the warlock that now gets the option to combine affliction/demonology/destruction which affords the warlock a certain amount of flexibility. The ability to dual spec into a demonology spec means that the warlock gains the ability to become a quasi tank via their pet (assuming the tree gets adjusted a little) and even though affliction no longer is what it was there's still the hope that it will provide some drain tanking capability. This means that to a certain extend the warlock can act as a weak off-tank and a strong dps depending on spec combinations.
Unfortunately this utility is still a long shot away from number 7 on the charts and in the end the warlock falls into the DPS = DPS trap resulting in the warlock having slightly more utility than a mage on the tanking field but this utility will most likely never be more relevant. I'd consider mages and warlocks tied on 8th/9th position but give the warlock the benefit of the doubt due to demonology potential.
#7 The Hunter
On 7 we find the hunter. With BM being a strong pet spec giving the potential to be quite a solid OT and two DPS spec the hunter seems to be in the same boat as the warlock capable of providing some pet tanking capacity coupled with solid DPS ability. What sets the hunter apart from the warlock in this regard is that the hunter's pets have benefitted from a more focussed talent tree and have talent trees themselves drastically increasing their utility (I'd trust my gorilla to tank a non-high end instance, my void walker? not so much).
Even though the hunter is still more or less a pure DPS class the added pet with own talent tree and a supporting character talent tree in BM it is clear that the hunter will be miles ahead of the warlock in terms of potential utility but still a far cry from number 6 on the charts.
#6 The Warrior
Warriors will have reason to rejoice come dual specs. No longer will they have to make the arduos choice between tanking and DPS but they can simply be both. With a significantly powerful tank spec that is also considered a viable PVP spec these days combined with the potential to do solid DPS a warrior will gain the ability to almost seemlessly switch from a tanking to DPS mode and more importantly vice versa.
Given the gear discrepancy however the warrior will have to drag 2 sets of gear around for each individual spec and unless specifically invited in a run as DPS will rely somewhat heavily on the protection spec. After all mid run it's more likely that you will end up needing another tank rather than needing you to switch out of tanking mode into DPS.
#5 The Death Knight
The death knight finds him/herself in the same boat as the warrior. With tanking options opening up via the frost tree and two alternate DPS specs the only real thing that sets the DK apart from the warrior is the higher utility of the blood/unholy trees that afford the death knight a much better survivability in solo play due to significant health return potential. The death knight may also benefit from being able to switch into an anti caster role quite easily giving it just that much more utility than the warrior affording it a slightly better place on the charts than the warrior.
#4 The Priest
The priest will be able to bring an incredible amount of utility to the table when allowed to dual spec. Combining Shadow and holy/discipline will turn the average priest into something that can both heal and DPS with almost no significant difference in gear itemization. This makes transitioning from DPS to healing a very smooth operation. Additionally the dual speccing priest will gain a significant amount of utility by being able to explore different healing specs and thus becoming a good shoe-in for any larger raid situation that will probably already have a certain amount of healers and be in search of the ideal spec to round up their group.
Traditionally the priest has had a high level of utility in any situation which can now almost be doubled with dual speccing options.
#3 The Shaman
At number 3 and maybe to some people's surprise we find the shaman. The ability to combine elemental powers with healing powers already makes the shaman a decent choice to DPS or heal even if the shaman isn't specced in one or the other. Once again the gear itemization helps to cover the gap between elemental and restoration allowing for fairly smooth transitions between ranged DPS and healing. The addition of enhancement could mean that the shaman gets the benefit of either filling the role of melee dps and ranged DPS which these days can be the difference between either participating or not participating in a run.
That's a tremendous amount of utility all rolled into one and this can be incredibly beneficial to any raid.
#2 The Paladin
It should come as no surprise that we find the paladin amongst the winners in dual spec. With each talent tree designed for a specific role the paladin can heal, tank and DPS with the best of them. Combining protection and retribution will turn the paladin into something that has literally all the benefits of a dual spec DPS/Tank warrior. Combining protection and holy will mean that the paladin will be 1 of only two character classes that are capable of switching from a tank to a healer role and vice versa which makes the paladin incredibly powerful and a highly desirable class for any raid. Add to this the already great utility of a paladin and the paladin ends up on a well deserved 2nd place.
#1 The Druid
The druid will be the character benefitting the most from the dual spec scenario and is literally the only character class that can fill all relevant roles in-game be it melee or ranged dps, healing or even tanking. A druid willing to drag around enough gear sets can potentially cover tanking + dps and healing in a single dual spec combination. Hybrid orientation can drive this even further in case of the druid.
Combine this with the tremendous base utility which the druid had anyway and I can strongly recommend rolling one of these if you want to make the most use of the dual specs.
So that's it, my personal top ten of character I anticipate will benefit the most from dual specs. Any thoughts?