And while it's not fair to say that shamans were broken at release... enhancement was and remains a lot of fun and restoration works fine, not tremendously flashy but solid and avoiding excessively good talents or mana regeneration that ends up getting nerfed later... elemental effectively rolled out of the gate missing a transmission, simply lacking in scaling abilities that other classes had and not getting them until 3.0.8's release.
Now, part of this problem has to stem from the concept itself. Some classes are easy to 'pitch' or boil down to their essence. Warriors hit things. Rogues stab things in the spine. Druids shapeshift and channel nature magic,. Paladins channel the Holy Light to heal or hit things. I'm massively oversimplifying, but when we come to shamans, there are several elements to try and get into our 'pitch' or otherwise it doesn't really sound like a shaman anymore. Shamans channel the power of the elements through totems to damage or heal is about as concise as I can get. You can't really leave the elements or the totems out and have it be a shaman, at least in WoW. It's not really any harder to execute than a druid, exactly, but the druid has the advantage of a powerful and easily explicated set of archetypical forms. There's bear form, cat form, moonkin form (lazer chicken!!!), tree form... you know what a druid is doing by what body they have.
Shamans lack this ease of identification. An enhancement shaman is wearing mail and dropping totems. An elemental shaman is wearing mail and dropping totems. A restoration shaman is wearing plate and dancing an elaborate magical dance to... oh, wait, no, he's wearing mail and dropping totems.
Another difficulty for the shaman class is its origin as the counter-paladin. For a very long time, shamans had talents like Shield Specialization in their enhancement tree, both to provide some benefit to elemental and restoration shamans who were speccing over into enhancement (both these specs are far more likely to use a shield, albeit a caster one, than a melee focused enhancement shaman) but also because at one point shamans were considered 'offtanks' for the Horde, fulfilling the same idea as paladins. Entire raid encounters were designed with the idea that a raid would have shamans or paladins, but not both: Horde-side tanks were using hamstring to proc Windfury well before Alliance even concieved of the possibiity. Their cleanse ability had to be at least within tolerable limits of each other, because if there was an encounter that heavily favored one of these classes over the other then the faction that lacked one would be penalized.
In theory (and often in practice) the decision to allow paladins to the Horde and shamans to the Alliance freed up both classes from having to be the bizzaro-world imperfect duplicates of each other. But while this means that shamans no longer have to be WoW's anti-paladins (and hey, DK's do that better anyhow) it does also mean that shamans, freed from that constraint, often seem to lack a clear and consistent design vision.
Elemental shamans have gone through the wringer, a roller coaster of up and down and up and down and up again that I hope is finally on an upward swing that plateaus into a strong contender for anyone who likes the ranged DPS role.
Enhancement shamans, with the introduction of dual wielding, went from the horde version of ret paladins (and I'll admit now, before BC, enhancement shamans were the burstiest burst that ever burst a clothies health to zero in one crazy WF proc on a Might of Menethil - mages and even warlocks would simply explode into dust when that one shaman with this mace showed up in a BG, not even a Naxx geared warrior could survive if the proc was also a crit) to a woodchipper class that traded ridicuous critical burst for a more even (still bursty, but more even than it was) class and their current interpretation as a melee class that does heavy magic damage is possibly the success story of the new shaman direction. There was a long drought, though, where enhancement shamans were second rate.
As for restoration, it was never a mirror image of paladins, its strength were always polarizingly different and probably served as the greatest motivation to decouple the classes. Perhaps that's why it seems to have never suffered the embarrasing lows the other specs have, but also has never really hit the heights either. (I know some folks consider resto to be OP, but to be honest, it's one spell most folks have trouble with).
In the end the decoupling was to the benefit of the class, but it also seems to have caused some serious growing pains for the design, as the sudden loss of the need to mirror another class left it scrambling for an identity of its own. Hopefully, we're all caught up now.
All of this is interesting, but it is what it implies for the future that interests me. What's coming for shamans past 3.1? Heck, we don't even really know all that's coming in 3.1. What will PvP utility be? Will there be changes to restoration to match the ones for elemental and enhancement? How far will totem streamlining go? Too far and we risk losing the flavor of totems. Are we ever going to see new totems? Perhaps an Earthliving totem of some kind to be a clear winner for healing shamans? Things are looking good going into 3.1 and I'd like to see that momentum continued rather than the disappointing state of the class (an entire tree poorly designed compared to its competition) when Wrath went live.
Next week I promise to be less head trip oriented and to talk about restoration more. It's a subtly changed talent spec in WoTLK and the more I play with it the more I see ways it's gotten stronger without being blatant about it.