My experience from Diamond 5 to 4k Legend (I've played standard only after expansion came out, and got Diamond in 1 day). I haven't seen a single priest. Lot's of DH's, Hunters, Shamans and Paladins. Warlocks are less popular than in the begining, but at day 1 it was liek 90% people playing it. Warriors, Rogues and Druids are kinda rare, but still vaiable.
I feel like next buffs / nerfs will change at least 12 cards.
Most likely they will nerf Mage and Warlock again, give DH and Hunter a buff :-) They want to make sure they are dead.