We will compile a bit all the things here. There are some huge changes and I think they will work well together.

Achievements

• We will have account level achievements!
• Some new type of achievements are going to be added.
  
• For example: Max out all the existing professions.

Classes

• Resilience will be a base stat, like str, int, agi and so on. You'll get a little bit of resilience with each level.
• Range item slot - GONE
• Relics - GONE
• Spellbook cleanup - DONE
• Rotations improved
• You auto learn spells. No more trainers to visit for that.
• Trainers are for respec and stuff like that only.
• Some new spell. We might get one at lvl 87, beside the one we will get for sure at lvl 90.
• Hunter
  
  • Min range - GONE
  • Melee Weapon - GONE
• Rogue and Warrior
  
  • They will be able to throw their melee weapons.
• Warlock
  
  • Unique resources for each spec
  • Affliction will use Soul Shards - cool ideas incoming.
  • Demonology will use Demonic Fury - you build up demonic fury and you hit max you Meta. You will get new abilities for demo. You can stay more in demon form.
  • Destro will use Infernal Embers - You catch on fire by casting fire spells. You will increase your dmg for big nuke when that happens.
• Shaman
  
  • Buff totems - GONE
  • All totems are about utility.
  • Three new totems added:
    
    • Earthgrab totem - roots
    • Repulsion totem - repels
    • Bulwark totem - absorbs
• Druid
  
  • Now they have 4 specs
  • Guardian is the new spec. That's the Feral Bear one.
  • All druids can still go cat or bear form.