Prior to TBC many classes were limited to a single spec, or possibly two if they wanted to raid.
- If you were a raiding priest, you were holy.
- If you were a raiding shaman, you were most likely resto.
- If you were a rogue you were combat.
- If you were a hunter you were most likely Marks.
- If you were a paladin, you were holy.
- If you were a druid, you were resto.
In TBC, Blizzard attempted to make offspec's viable in raids, and in many cases were successful. Shadow Priests, Enhancement Shaman, BM Hunters, Feral druids are all examples of specs that previously would have been laughed out of raids, that are now very powerful and useful. From what we know of WotLK, Blizzard is even more aggressively pursuing this train of thought, not only in raid viability, but also PvP to some extent. A Discipline Priest will not only be viable, but will be sought after as a main tank healer. Assassination looks like it very well could be the new highest dps Rogue spec. Additionally, PvP tools are being spread around to all the trees. Fury warriors have Heroic Leap, Feral Druids have new tools, and Enhancement Shaman get all kinds of toys.
There are 10 classes, with 3 talent specs each, bringing us up to a whopping 30 different "specs" that they are trying to balance for both raiding and PvP. In a perfect world, this would be great. Blizzard would actually have the manpower and time to tweak every single talent spec and make them viable in both raids and pvp, and the players would have a large number of ways to play their class in both the raid and pvp environment. In the real world, we all know that's unlikely.
Is it smart for Blizzard to attempt to simultaneously balance 30 different specs for 2 different venues? Why not simply tighten up their focus to 10-15 specs per venue, and theoretically get the fixes to us faster and reach "class balance" in each area far sooner? Do we really need 2 different dps flavors of warriors both viable in pvp and pve? Why not move Blood Frenzy to Fury, Heroic Leap to Arms, and simply tell warriors "If you want to PvP, go Arms. If you want to raid dps, you are Fury."
Wouldn't is be much simpler to focus on 1-2 specs per class per venue and make sure they do it right?
Warriors:
I want to PvP - Arms
I want to tank - Prot
I want to PvE dps - Fury
Priests:
I want to dps - Shadow
I want to raid heal - Holy
I want to pvp heal - Discipline
Hunters:
I want to PvP - Marks
I want to dps - BM
I'll sacrifice personal dps to significantly boost raid dps - Survival
Looking at just these three examples, do Warriors really need 2 different dps trees viable in both raids and pvp? Do priests really need two different raid healer specs? Why not keep each tree focused on a "job" (pvp or pve) and consolidate all the neat tools in one place, instead of spreading them across 2 trees and doubling how many specs you are trying to make raid/pvp viable?