I am a MT group defiler. I currently am set up in the Wis and Str line. The aoe immune and wards are still worth it on most mobs. The Wis line has turned out to be quite useful to me after last patch. I can now wear the unrest buckler in case I get hit a time or two and also have my heal booster. That booster also boosts your cannabalize if you have that in the EoF tree. The MT LOVES me to cast the final spell in the Wis line on him at pulls. It boosts his dps and helps him keep aggro a little better with his spells hitting faster and refreshing faster and at a minute and a half I can usually get it on him most pulls. I also like speeding up my own refresh times along with the stat buffs - an all around good line now. Plus you get Wis!
As for EoF I went soul ward and cannabalize - if you know how to use soul ward it will end up saving wipes for the raid countless times. It takes practice to get good at it though. And for cannabalize, I don't use it every fight, but on long fights it is HUGE - I don't even have to worry about hearts and shards too much with that ability if at all. I have good FT but still like the cannabalize - you can never get too much mana - only downside is that its a fairly long cast time - but 20 second refresh! Thats 14% mana every 20 seconds if you combine it with the Wis 2 effect.
There you have my set up - I'm sure others have theirs set up different - take what you like and run with it .
Gamble 70th Defiler -Butcherblock
Estean 70th Necromancer Butcherblock