Well, most of them quite expected and reasonable. I think Ancient of Lore could have its cost dropped by 1, like they did with Force of Nature, but I guess they reason that Druid has access to more and cheaper mana than other classes.
Hunter’s Mark and Blade Flurry was surprising ones to me. Someone pointed out that Mark is now in line with Soulfire and Execute, but I wasn’t under the impression it was seeing a lot of play anyway. Perhaps they are expecting control Hunter to be a thing now. Flurry seems like a similar situation. Both Hunter and Rogue are getting a slew of high-value cards, so maybe it’s pre-emptive. I still think Flurry could have been fine with either of the changes though, 4 mana OR can’t damage face. Both seems like a huge hit.
Arcane Golem was probably deserved, but now it’s completely unplayable. That’s a bit sad. Decks that really want to can still run Leeroy.
Molten Giant was another surprise to me. Again, it seems they are expecting control decks to return big time, and Handlock was often the control deck that could out-control other control decks. With this nerf, you can still play double molten and taunt up, but you need to be at at least 9 HP with Sunfury Protector (4+4+2) or 8 HP with Defender of Argus (3+3+4). And you might run Thaurissan too. With BGH nerfed, dealing with biggies is more costly (BGH will definitely still be played, but it will slow you down), so it might not be an unreasonable change.
Overall, good changes. The potential for a considerable slow-down of the meta seems quite high now. All the major aggro decks are getting hit quite hard:
Hunter: Gnome, Juggler, Golem
Shaman: Crackle, Zap-o-matic
Paladin: Juggler, Minibot, Muster
Druid: Juggler, Combo
Zoo is not aggro, but it’s probably going to be one of the faster decks anyway. Hunter will find a way, I’m sure. Shaman might too, since they still have a bunch of damage spells in reserve.