I don't think THM or CNJ will be getting/keeping the Elemental Nukes. Instead I believe SE is going to pull them until patch 1.21 when the Black Mage Job comes out. I realize THM is the class that will Unlock BLM but that being said, THM is NOT a Black Mage....it's a Thaumaturge. THM/CNJ will retain an identity that is separate from the Job it unlocks...albeit, related to the job.
Because of this, I think THM can expect to keep:
Scourge and Banish and Shadowsear as their DD spells (3)
Sacrifice and Drain as their Healing Spells (2)
MP syphon and/or Stygian Spikes (1 maybe 2)
Poison, Dia, Bio, as their DOT's (3)
as to Debuffs the most likely to remain THM are Gravity, Slow, and Paralyze, but I expect THM to keep 3-4 of their current list of these. (3-4)
1 WS or Magical ability that works as such. (1)
Also, SE will probably make sure that each class gets at least 1 brand new skill.