To-do list (Try to keep the order by importance)

Reputations
Achievements / Guild Acievements / Implement acc achievements
Update ingame damage / stats calculation, (including newest formulas from paper doll)
Implement dynamic update fieldss
Implement PvP Power / Update resil
Battlegrounds
Implement Premade characters
Instance Locking
Professions
Void Storage
Arenas - needs full rewrite O.o
Pets / Pet Battles
Scenarios
Ingame Shop
Archaeology
Rated Battlegrounds
Dungeon Finder
Guild Finder
Raid Finder
Implement char boost

Finished Stuff

Auth
Char Enum
World Login
Talents / Known spells
Char name / Realm queries
Messagechat
Basic player movement
Implement addons packets - To prevent ingame spam
Teleporting / Move speed changes - SMSG movement
Creature/Gameobject queries
Creature movement
Combat / Autoattack / Attacker stats ...
Item swapping / equiping
Gameobejct transparency (general bug - not structure related, wrong values in update fields)
Spell casting / casting results
Auras
Creature / Gameobject gossips (including vendors and trainers)
Glyphs
Properly finish living part of object update
XP Related Stuff
Loot
Groups (Parties / Raids)
Mounts
Guilds
Quests
Mail
Auction House
Bank / Guild Bank
Transmogrify
Calendair & Events