Patch 4.2.0 (undocumented changes)

General

 * Due to Burning Crusade status being granted to all accounts, level 60 characters who could previously queue for a random classic dungeon through the dungeon finder can now only queue for a random Burning Crusade dungeon instead.
 * Checking your mail, opening your map, or typing /read (but NOT typing the /map emote) now plays an animation of your character unfurling a map.
 * New hairstyles have been added in the barber shop for the following race/gender combinations:
 * Night Elf Female: Sassy Buns, Sassy Tails
 * Gnome Female: Punky
 * Gnome Male: The Curl, Blade's Edge, Fauxhawk
 * Dwarf Male: Triple Knots, Tousled, Combover
 * Dwarf Female: Wings, Sassy Buns
 * Draenei Female: Slicked
 * Blood Elf Male: Short (previously listed as "Slicked")
 * Blood Elf Female: Braided Tail
 * Tauren Female: High, Omega, Backswept
 * Troll Male: Balding Braids, Dragon's Crest, Falling Fauxhawk
 * Troll Female: Sticks & Stones, Backblown
 * Undead Male: Wedge
 * Orc Male and Orc Female had new hairstyles on the PTR that did not make it to the live patch.
 * Jin'do the Godbreaker now warns "Jin'do charges his weapon with the Shadows of Hakkar!" whenever casting Hakkar's Shadow.
 * Companion pets that cannot fly are dismissed when lifting off the ground on a flying mount (but not in flight forms) and return when you dismount.
 * Burning Crusade heroic dungeons no longer (indirectly) require certain reputation levels due to the removal of the keyring. The former attunement quest Hard to Kill for Magisters' Terrace still exists, but is no longer necessary to enter the dungeon on heroic difficulty.
 * The gate of Karazhan no longer requires The Master's Key. The former attunement questline to acquire the key still exists.
 * Feline companion pets have sitting and lying idle animations.
 * Avian companion pets have had their flapping speed reduced.

Achievements

 * Two new achievements for the Hallow's End holiday event have been added: Tricks and Treats of Northrend and Tricks and Treats of the Cataclysm.
 * New reputation achievement Time Flies When You're Having Fun for becoming exalted with your guild.
 * The Justly Rewarded achievement now retroactively recognizes previous quest reward amounts.
 * The Guild Achievement United Nations has been reset, and now lists which reputations need to be exalted in order to qualify. It also no longer requires all 55 reputations to be held by a single character. However, the achievement is now worth 0 guild achievement points.
 * Four masks have been added to A Mask for All Occasions a male and female mask for both Goblins and Worgens.
 * The Cooking Achievements Let's Do Lunch: Darnassus, Let's Do Lunch: Ironforge, Let's Do Lunch: Thunder Bluff, Let's Do Lunch: Undercity, A Bunch of Lunch (Alliance) (Alliance) and A Bunch of Lunch (Horde) (Horde) were added, and the faction-specific Cooking Achievements both named "Let's Do Lunch" have been renamed to Let's Do Lunch: Orgrimmar and Let's Do Lunch: Stormwind.
 * The Fishing Achievements, , , , Gone Fishin' (Alliance) (Alliance) and Gone Fishin' (Horde) (Horde) were added, and the faction-specific Fishing Achievements both named "Fish or Cut Bait" have been renamed to Fish or Cut Bait: Orgrimmar and Fish or Cut Bait: Stormwind.

General

 * Permanent pets no longer despawn when mounting and riding on the ground, but despawn when the player takes flight. In addition, the last used hunter pet will always be shown on the login screen even if not at the master's side when the player logged out (possibly intended for at least warlocks as well, but not working).

Druid

 * Prowl now once again begins its cooldown once the druid leaves Prowl. (Note: for rogues' Stealth, this is indeed in the patchnotes, but not for Prowl).
 * Balance druids can now move change the direction of their Eclipse meter when starting fresh (either from zoning in, or having recently died) up until they reach their first Eclipse state, at which point the eclipse meter will only move in a single direction. Starsurge will continue to select the most advantageous Eclipse, but will always prefer Solar over Lunar when starting from exactly 0 energy.

Hunter

 * The initial cast of Misdirection now produces a healing sound.

Paladin

 * Rebuke will now cause the character to perform the uppercut-animation instead of the kick-animation.

Priest

 * Divine Aegis now uses the same spell effect as Power Word: Shield.
 * Chakra has a new icon.

Warlock

 * Soul Shards no longer disappear if Mass Resurrection (guild perk) is cast and accepted after the warlock has released.
 * Rain of Fire has a new spell effect.

Molten Core

 * Ancient Core Hounds have been renamed to Core Hounds.
 * The Core Hounds in the packs before Magmadar have grown much larger.

Player Versus Player

 * Reputation earned in Arathi Basin is now earned for every 260 resources (250 during Call to Arms), up from 160/150.
 * If you are not flagged for PvP and you buff a player who is flagged, you stay unflagged.

Items

 * Crafted gems now stack.
 * Horde Balloon and Alliance Balloon companion pets have been added to the game. Speak with in the Valley of Wisdom, Orgrimmar or  in Cathedral Square, Stormwind to start the quest, Blown Away to obtain them.
 * Winged Guardian now has a unique icon.
 * The MiniZep created by MiniZep Controller can no longer fly in areas where flight is restricted, such as battlegrounds and dungeons. It can still fly in areas that allow flight, even if the controlling player has not learned the appropriate flight skill for the area. MiniZeps that cannot fly can still jump.
 * New Vicious Gladiator Season 10 gear, i371, has been added as of the start date of arena season 10 on July 5th, 2011. The new gear has increased statistics to maintain the alignment between conquest purchases, Ruthless Gladiator i384, and honor purchases, the new Vicious Gladiator Season 10 i371.
 * The undocumented change was questioned by many who spent honor and gold (for gems, enchants, and reforging) and would have saved for an additional week had they known of the changes. Blizzard has not yet determined if or how to compensate for this change.
 * Mature Spore Sac is now Bind on Pickup and can no longer be sold or traded.

Cooking

 * The ability to make Sporeling Snack s has been removed from the game, and Recipe: Sporeling Snack in a player's inventory has been changed into a Ruined Recipe, a gray quality item. Existing Sporeling Snacks in an inventory have also become gray items with no use, and their flavor text have changed from "Pets love sporeling snacks!" to "Pets hate sporeling snacks!"
 * Kibler's Bits has been changed to just make your pet larger for 5 min, from previously increasing your pet's happiness (the happiness-system was removed in 4.1).
 * Items purchased with Chef's Award have been added to Cooking Supplies vendors in Darnassus, Ironforge, Thunder Bluff and Undercity (previously limited to Stormwind City and Orgrimmar).
 * Recipe: Dig Rat Stew and Recipe: Undermine Clam Chowder have been reimplemented with new sources.

Jewelcrafting

 * Fire Prism has been moved to the Consumables tab in the Jewelcrafting skill pane.

Mining

 * The skill required to mine and smelt ore has been reduced for most vanilla ores (i.e. tin through thorium).

World Environment

 * Portals to Orgrimmar and Stormwind have been added outside the Nordrassil Inn in Mount Hyjal.
 * The red glow at the top of the castle towers in Stormwind City doesn't glow as much as it used to, and the wood texture of the castle tower has a newer look to it.
 * The mini-map in this area also has had some refinements, including orange for the castle towers.
 * A new pub, the Shady Lady has been added to Stormwind's Dwarven District. Because really, you can never have too many of those.
 * , the owner and proprietor of the Shady Lady, now sells off-hand wine glasses that could previously only be found in Dalaran. And yet, somehow he could only afford to buy the top half of his outfit.
 * The alley itself of Cut-Throat Alley is no longer part of the Cut-Throat Alley subzone, which now only encompasses the empty two-story building within it.
 * All the molten giants (such as Molten Destroyers, Molten Giants (mob) and Golemagg the Incinerator) have had their model updated.
 * The Ruins of Lordaeron has been populated with NPCs: Undercity Citizens, Kor'kron Overseers, Apothecary Initiates and Forsaken Apothecaries.
 * Some Hero's Call! and similar breadcrumb quests automatically unlock the flight paths for the destination quest hub.
 * The fishing pools at Schnottz's Landing are no longer affected by phasing and can now be seen by any player within the subzone (the phasing would previously cause the pools to turn invisible to players who hadn't completed the necessary quests). The Shrine of Goldrinn is however still suffering from this problem (herbs inside the zone turn invisible to some players when they enter it), implying that Schnottz's Landing was merely a location change, and not a phasing-mechanics change.

User Interface

 * Added a Battle.net icon in the Social Pane.
 * Flight Points
 * The map's Flight Point icon has slightly changed to make them stand out a little better.
 * Missing Flight Point icons has been added in the game map to multiple locations including Azure Watch, Blood Watch, Exodar, Booty Bay, Karnum's Glade, Nethergarde Keep, Flamestar Post, Shattered Sun Staging Area, Theramore Isle, Menethil Harbor, Zul'Aman, and all Outland and Northrend zones.
 * Flight Point icons which were previously shown as neutral where there were individual flight masters for each faction (such as Cenarion Hold and Gadgetzan) has been changed to the faction-colored Flight Point icon.
 * Alliance/Neutral Flight Point icons have been slightly realigned in many locations including Blackfathom Camp, Dolanaar, Rut'theran Village, Windshear Hold and Wildheart Point.
 * Flight Plan icons not for your faction no longer display on the map.
 * A new flight point has been added at the Sanctuary of Malorne.
 * Added Swim Point icons and Flight Point icon in Vashj'ir.
 * Re-added Flight Point icon in Badlands.
 * Stormwind's banner on the Elwynn Forest and Stormwind City maps has had a slight text cleanup.
 * The location of the Track Quest check-box on the map has moved slightly to the right.
 * There is a new sound effect for changing talent specialization.
 * The Blizzard raid frames now show an icon on a dead character who is being resurrected.
 * Added a map of Black Temple.
 * Full-grown dragons, such as have new portraits.

Bug Fixes

 * s,, and no longer have death knight eyes.