First of all, the quests, while numerous, were unoriginal and uninspired. The overwhelming majority of them followed the same format Blizzard have used since Vanilla. Kill X of something, collect X of something, pick up poo, do the safari, etc.
I don't pvp, so I won't offer any comments on it, however I haven't heard anything new and exciting. Seems to be people just complaining about the flavor of the month dominating. Nothing new here
Dungeons are completely irrelevant after you hit ilvl 460. You don't grind them for valor, Justice is completely worthless and you get 0 rep from them. The time investment isn't even remotely worth the amount of gold you get.
Scenarios are even worse, because not only do they offer no benefits like dungeons, but they only have a 10% or whatever chance of you even getting a reward.
Dailys are so long, so boring, and give so little. Definitely not the worst grind I've gone through *cough* insane *cough*, but for borderline mandatory content it's excessive and there's only one option to do it. If I could grind rep in dungeons with friends I would. Once they're all done we're not going to do them again, but we will prob be given another 2 hours of borderline mandatory dailys in a future patch
Pet battles are new, but just like the game it's based on it's far more affective to just steamroll the npc's. Pet battle's in PVP is simply a case of queue up, wait 10 minutes and then your opponent forfeits unless he has a huge type/level advantage to your pets. Neither of these things are very fun or exciting
Farming is mildly interesting but extremely limited and repetitive. First couple day's its kinda cool, then you just do the same thing every day
So now at level 90 with 460+ ilvl. gear i'm finding myself bored out of my mind. What do I do after my long arse 2 hour dailys grind? Do I level an alt through the million new quests that give no XP while all the other insanely bored 90's fly overhead pouncing on everyone while they wait for their queues to pop? Do I queue for dungeons/scenarios I don't need? Do I queue for pet battles hoping someone will stay long enough for me to get a win?
The only new activity I would do more of would be farming but I'm locked out for a day and alts can't get any rep from it