ok, so I'm not a theorycrafter, but looking at the talents, it seems they offer you new playstyles to the old specs.
For warlocks, Chaotic Resources does this to demo: "Touch of Chaos no longer costs Demonic Fury, and instead generates 40 Demonic Fury, but Metamorphosis provides 30% less increased damage."
since touch of chaos refreshes corruption, that means you'd place corruption, pop meta and never have to worry about going out of meta again. it's essentially a permanent metamorphosis. a non-stance dance version of demonology.
For Hunters, With or Without You allows MM and SV to be petless hunters.
Cat Druids with Touch of Elune can now cast moonfire in cat form for 30 energy generating one combo point. that breaks one of Alamo's rules:
"and CAT DURIDS is no spam moonfare! Sum cat durids dosent no wut is uh moonfare!"
Shadow Priests can now opt out of the DoTing dps style with Divine Clarity, which greatly enhances their direct spells on targets that do not have any of your DoTs on them.
Finally, the Seal of Faith is there to, apparently, give paladins the "dps for heals" style that disc priests and monks enjoy. on this one, you beat the boss for some time and gain spellpower equal to your damage done for your next healing spell. It always made sense that paladins would be beating people up and than healing others, and blizzard has previously stated that they think the atonement style fits paladins well and should be brought to them. now that is here
In my opinion, these talents are rather neat. they are much more game changing than any others! of course not every talent should completely redefine your spec, but I believe that the more playstyle choices we have, the better and more fun the game will be. especially now since we got no new class and no new specs - many of us will feel the need to try something different, while others don't want to have to re-learn to play. these talents can deliver to both kinds of people! take the talent if you want a new playstyle or take another talent if you don't. (that is, assuming that they'll be well balanced and there won't be a clear winner)
so, what do you think? do you welcome new playstyles to your class? do you dread the thought of being forced to play a different style for a 5% dps increase? do you wish your class had gotten new playstyles too?