When a developer nerfs classes it illustrates one of two things. Firstly, it is illustrating their incompetence as developers by not following the Sofware Development Life Cycle in that the developers did not plan out their game well enough. Secondly, if the developers did plan this into their game, then it shows a lack of respect for the time investment of the player base because the developers are intentionally nerfing to create flavors of the month.
First a nerf to the magicka cost of Vampiric drain. Then a nerf to the Death Stroke so it doesn't give a crit bonus from stealth. None of the nerfs have effected my character build in this patch, but if they had I would have been gone.
I'm not going to have a hobby where the value of my time investment into my character, which is significant, can be wiped away with regularly implemented Cracker Jack nerfs. You will loose a lot of customers if this company keeps it up. Remember Ralph Koster (Ultima Online, SWG)? That clown publicly endorsed Flavors of the Month as a way to encourage the player base to see his old content through the eyes of a new class. Does this company want to follow the way of the Koster.... I mean the dodo as well?
My condolences to those of you who have spent 100+ hours creating a character only to have it changed into an nonviable build.