Below you can see a changelog, which was made on 5.4.8 for 2 months, from 11.04.15 to 24.06.15:

Status: applied on all realms.

List of changes:

General:

- Fixed a bug where sometimes it was impossible to buy items for the various currencies such as Spirit of Harmony.
- Modified functionality of NPC for getting complex achievements.
- Implemented new achievement system, now you can get almost all achievements in the game.
- Again fixes to exploits where character stats increase with reset talents.
- Modified checking of loot available for players.
- Fixed exploit which allowed using some spells to increase the speed and run like on speed hack.
- Fixed exploit related to the objects http://www.wowhead.com/item=86587 / http://www.wowhead.com/item=86572 / http://www.wowhead.com/item=86570.
- Implemented the possibility to change the guild leader, if he was not for a long time in the game.
- Again fixes to mouvement on mounts after death and reload.
- Fixed generation of gold in loot from mobs and bosses for group/raid (one of the final steps in the restoration of the economy).
- Implemented checking for transmogrification of legendary items.
- Fixed displaying of transmogrification after reload.
- Implemented funktion "Pass on Loot".
- Fixed exploit with increasing of armor.
- Rewritten quest system for a blizzlike realization Warlock's questline The Codex of Xerrath, the beginning already done.
- Fixed bug with titles, which players can get but cannot use.
- Implemented the possibility transmog legendary items, now it can be done via a special NPC, which stands in the capital city (near NPC for the usual trance), the cost of one item trance 20,000 gold.
- Fixes in the achievements system, should start working new of it, where there were requirements for a particular faction.
- Realized work most of the guild achievements.
- Fixed bug with raid markers.
- Fixed Auction House search (in theory) for all languages. Need to test.
- Implemented basic scenarios system and their achievements. Now available Theramore's Fall scenario foe Alliance (as a test), after tests all scenarios can be implemented very fast.
- On Isle of Thunder now impossible to enter, if character level lower than 85.
- Fixed item http://www.wowhead.com/item=100910.
- Fixes to enchants and elixirs which scaled your power depending on the characters level.
- Implemented cooldown for spell http://www.wowhead.com/item=98163.

- Fixed 8 reasons for server crash.

- All Data Base fixes - quests, creatures, loot - you can be seem in this section http://forum.pandawow.ru/forumdisplay.php?f=224&page=2 (from 14.04.15 to 22.06.15), with messages from Herald.

Instances and raids:

Throne of Thunder:

- Implemented the basic work of all bosses in this raid, within a few days will add achievements and loot, also woll be open access in Heroic mode.

Siege of Orgrimmar:

- - Implemented the basic work of this raid. At this moment implemented first 2 bosses Immerseus and Fallen Protectors, after testing period will adding loot and achievements (during the week).

Instances and raids, others:

- Implemented Oondasta script, loot already added.
- Fixed loot in the dungeon Scarlet Monastery.
- Fixed bug, when mass resurrection can be applied during a fight with boss.
- Fixed bug where you cannot move players to other group in raid interface.
- Fixed bug where players role in raid interface displayed uncorrectly.
- Fixed bug where characters stuck after teleportation in dungeon.
- Fixed bug in http://ru.wowhead.com/zone=5334/ where players could open the door without killing the boss.
- Fixed creatures for 5ppl WotLK dungeons (normal and heroic).
- Fixed possibility to reset raids cooldowns (without killing bosses) by changing difficulty.
- Fixes to calculation of the coordinates for mobs in instances, it should fix problems where boss can fall through the floor in texture.
- Now you don't get cooldown, if data of instance changed, but bosses still alive.
- Fixes in Scholomance: fixed exit from the instance, fixed respawn on the graveyard after death, rewritten boss http://www.wowhead.com/npc=59184.
- Fixed cooldowns for instances, raids with one difficulty (Black Temple and so on).

Battlegrounds and Arenas:

- Added missing objects at BG Temple of Kotmogu, for example Berserking.
- Fixed RBG working for low lvl characters.
- Fixed work of arrows and carts on BG http://www.wowhead.com/zone=6126-
- Fixed bug where taking and drop the flag on BG http://www.wowhead.com/zone=6665 has take the points of other command + was fixed taking the points for interaction with carts.
- Fixes for spell http://ru.wowhead.com/spell=26013 (changes duration depending on the number of leaving).
- Now if player don't accept invitation to RBG he get http://ru.wowhead.com/spell=26013.
- Fixed bug where after BG player can get too much Honor points or Conquest points.
- Battle Fatigue should be applied in case of getting damage from another player.

Spells and talents:

Mage:

- Fixed radius for spell http://mop.wowroad.info/?spell=113724.
- Trying to fix bug with 2 talents http://www.wowhead.com/spell=116011 + Invocation.
- Fixed visual displaying of talent Ring of Frost for other players + other the same spells.
- Fixed bug with talent http://wowhead.com/spell=108978 and dispelling.
- Fixed bug where http://wowhead.com/spell=84714 followed the target and didn't change it.
- Fixes to talent Ring of Frost.
- Added limit movement flag for Ring of Frost, fix problem, when it escape.
- Fixed the movement of sphere from spell http://www.wowhead.com/spell=84714.
- Fixed checking position for spell http://www.wowhead.com/spell=113724.
- Now if the player is in the cyclone and at him casts http://www.wowhead.com/spell=113724, then he has immunity to 3 seconds after the recession of the cyclone that not to be frozen.
- Fixed looks at the mage copies created by the spell http://www.wowhead.com/spell=55342.
- Immunity аura Ring of Frost after spell Ring Frost now has duration 3 sec, and not 2.5.
- http://www.wowhead.com/spell=113724 now correctly disappears from the dots.

Monk:

- Fixed http://mop.wowroad.info/?spell=115460.
- Fixed http://mop.wowroad.info/?spell=123904 - now it cast Lightning Bolt correctly.
- Fixed states for http://wowhead.com/spell=123904 and their depending on the owner.
- Fixes to spell http://wowhead.com/spell=117952.
- Fixed bug where the monks could heal other players spheres during their duel.
- Rewritten spell work http://www.wowhead.com/spell=124255.
- Number of healing from spells Gift of the Serpent now equal to half of the healing Healing sphere.
- Increased radius appearance of spheres of mastery http://www.wowhead.com/spell=117907.
- Fixed exploit with sphere of life.

Priest:

- http://www.wowhead.com/spell=131556/sin-and-punishment now do not have diminishing.
- Fixed mechanic http://wowhead.com/spell=15286 for players in the group.
- Fixed bug when spells of type http://www.wowhead.com/spell=527 sometimes there was no cooldown.

Paladin:

- Fixed paladin bonus set http://mop.wowroad.info/?spell=138238.
- Fixed scaling http://mop.wowroad.info/?spell=138242 from power of light.

Shaman:

- Fixed spell absorbing http://www.wowhead.com/spell=108270.
- Fixed calculation formula for mana regeneration for spell http://www.wowhead.com/spell=52127.

Warrior:

- Fixed a bug with increased healing from http://www.wowhead.com/spell=58382.

Warlock:

- Fixed interaction spell http://www.wowhead.com/spell=17767 with spells Grimoire of Sacrifice and http://www.wowhead.com/spell=119898.

Hunter:

- Fixed spell http://www.wowhead.com/spell=58605/lava-breath.

Spells and talents, others:

- Temporarily disabled some checks for spells stacking (need more fixes, that variant is bugged).
- Fixed bug where buying for currency was impossible, for example vendors http://www.wowhead.com/npc=66678 and http://www.wowhead.com/npc=66685.
- Rewritten and again implemented checks for spells stacking.
- Implemented fixes for haste where you will get a correctly haste rating from items and auras.
Fixed bug with haste.
- Fixed haste rating for ranged attack and empowerment on her various auras.
- Fixed bug where spells which modify casting speed worked not correctly.
- Fixed formula for mana regen spells.
- Implemented cooldown for spells: Swordguard Embroidery, http://www.wowhead.com/item=98163, http://www.wowhead.com/spell=33333 (fix to priest bonus set).
- Fixed calculating of miss chance for spells.
- Fixed bug where character had problems with energy after re-speck.
- Implemented a special flag which schould help with targets in a cone in front of the caster.
- Fixed dodge and parry chance for all classes.
- Fixed http://mop.wowroad.info/?spell=20572.
- Fixes to visiblity, features of pets visibility should apply only to the players.
- Fixed bug when expertise have incorrect calculations.
- Fixed displaying of spells accuracy.
- Now server's spell hit depends on the expertise.
- Fixed http://www.wowhead.com/spell=126392.

Don't forget to clear the cache of the game after the update.