Hard to get a complete feel till fully geared, but since I have less defensive cds along with the nerf to blood shield we seem weak, and the game play is fairly boring atm. They have just taken to many abilities away.
Speaking from 5man healing exp. A good DH tank can hold their own... though sometimes I do get a slight heart attack... before they heal themselves from 20-90% in a gcd (I dpsed. for 70% of fights cuz I had nothing else to do). Tho Im sure their self healing will be slightly nerfed. (A bad DH is suuuuuper squish tho... like pancaked on some fights) Bears are lovely to heal too but actually need external heals but its not like their hp is bouncing everywhere. They seem to have trouble picking up multiple adds at a distance (may have been just unobservent tanks tho) DKs are hard to say how they are now, havent healed one since some big changes rolled out. Havent seen many warriors around, but the one I did heal was decent. Monks seem to be all playing WW. Pallies are also quite good. Never had a "o shit shit shit" moment with one yet.
Havent really played any to any real extent tho, so do take it with grain of salt since my info could be skewed by dumb/god tanks.