Warlocks have been left behind in SOD
The setup
Metamorphosis costs 923 mana to activate (Every time I mount I have to reactivate Meta form).
Demon armor costs 800 mana to activate.
Summon Succubus cots 923 mana and a soul shard.
My mana pool is 2672. So after casting my required abilities, I have 26 mana left. Which means that in order to have my required setup, I have to drink 2 times before I am ready to fight at 100%.
In battlegrounds, Metamorphosis and Demon armor takes three quarters of my mana pool to reactivate before I can join the fight after a death. Every other class simply casts their buffs and still have over 90% of their mana or are 100% ready to rejoin the fight immediately.
In world PvP, it is a full round of buffs and you are required to spawn, run an entire minute away from the fight, and then take 2-3 minutes to prepare, before you can run back to the fight.
In short, it takes 2 water, a soul shard, and 2-3 minutes of time to restart after a death. This is nowhere near any other classes restart requirements.
The PvP Experience
Affliction is a worthless spec. Dots deal 400 damage over 30 seconds while every other class in the game can instant cast 600-900 damage. Scaling is non-existent with affliction abilities. You absolutely will not kill anyone with affliction.
Destruction abilities are strong in damage. However, they all require extremely long and punishing cast times. Destro warlocks are the only class in the game currently that are required to hard cast all of their abilities. When you multiply cast times + destro damage, you always end up lower than all other classes in PvP. Actually being able to let off a single 2 second cast in PvP is basically a one in a million chance. Warlocks are the first class targeted in every encounter because everyone knows how helpless they are.
On top of destruction having cast times, being able to fear anyone is also impossible. With everyone having insane mobility and instant casts, warlocks die before they can let off a fear. There are no talents or runes to help with damage knockback on hard casts, you create a worthless pvp class.
Metamorphosis is the only way warlocks are able to join PvP. However, spamming searing pain is less damage than all other classes and the self heals are atrocious and are not scaling with damage output from other classes. Healing 100 damage a second sounds good, but when everyone is instant casting 600-900 damage, it becomes completely worthless. Not to mention the setup requirement for meta in battlegrounds means that they are the worst class to play. While everyone simply waits 30 seconds for the res timer, meta locks must spend an additional 2 minutes drinking before they can fight.
Also, searing pain spam is easily the most boring class rotation in world of warcraft history. 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,1… Get my point?
Even with Meta, Warlocks are bursted down in a mere 3 seconds by spell damage. Mages walk all over us and there is zero chance against a boomy or priest.
The PvE Experience
Finally, we have a small niche that warlocks do alright with. Destruction warlocks regularly hit top 3 dps in raids. That sure is nice, but again, the playstyle is incredibly punishing and mentally taxing. Hard cast times on these boss fights that require CONSTANT movement is horrible. The other classes simply click their buttons and run in circles. Warlocks must retire their entire damage output with every 1 inch movement.
Then on top of that, dance of the wicked was demolished. Now warlocks must life tap after every second rotation in order to stay in a long fight. This is not only punishing for the warlocks, but makes raid groups think twice before taking a warlock because it puts immense pressure on the healers to keep the tanks AND the warlocks topped off.
EXTRA
What in the hell is Shadowflame? Lots of people were excited when Shadowflame was datamined. Now that we have it. It literally does 130 damage over 8 seconds.