The 64bit client is still in beta but details on how to run this will be released soon. I am really looking forward to the 64bit client as it should enable faster load times once inital content is cached as well as more UI mods with less worry on hitting the 2gb memory cap of a 32bit program.
The other huge bonus is the new Battletag / RealID raid system where you can raid with anyone in the game no matter what realm they are on.
Full patch notes below:
World of Warcraft Patch 4.3.2
Notes for all World of Warcraft patches can be found here.
Vengeance is no longer triggered by receiving damage from other players.
The Tier 13 Balance Druid 4-piece bonus now also increases the damage of Starsurge by 10%, in addition to its current effect.
Aspect of the Hawk now grants roughly 35% more attack power.
Deterrence now also reduces damage taken by 30% while active.
Black Arrow now ticks every 2 seconds for 20 seconds, as opposed to every 3 seconds for 15 seconds. The total damage dealt by the ability is unchanged.
Lock and Load no longer benefits Arcane Shot, nor is it consumed by Arcane Shot.
Fireball damage has been reduced by roughly 6%.
Pyroblast damage has been reduced by roughly 6%.
Holy Radiance now costs 40% of base mana, up from 35%.
Mass Dispel should again prefer dispelling targets that have magic effects that can be dispelled.
Adrenaline Rush no longer triggers a global cooldown.
Dungeons & Raids
You can now form same-faction raids with Real ID friends, allowing you to enter Raid Finder in groups larger than 5, run older normal or heroic raids, or participate in Battlegrounds. You will not yet be able to run normal or heroic Dragon Soul with cross-realm raids of Real ID friends.
Several typo fixes and clarified descriptions have been added to the Dungeon Journal entries for Dragon Soul.
Players can no longer win multiple copies of the same item on a single Raid Finder boss kill. For example, a player who chooses Need on two set piece tokens or two weapons and wins the first, will not be eligible for the second on that particular boss.
The roaming Eyes of Occu'thar have been replaced by hateful creatures who serve Alizabal.
The visual warning for Twilight Elites' Blade Rush should be easier to see.
Vial of Shadows damage (Lightning Strike) has been reduced to approximately one-third of previous damage. However, it will now trigger approximately 3 times as often. This is intended to keep overall DPS the same while reducing burst damage, especially in PvP.