Patch 4.3.2 is at hand, and you can find the full list of patch notes after the cut. If you haven't been keeping track, this is not a content patch; it just updates some features, fixes some bugs, and adds the new 64-bit client
(finally). Also of note: Players can no longer receive two of the same item at the same time when winning loot from a Raid Finder boss, Vengeance no longer acts off player damage, and Aspect of the Hawk got a big ol' buff.
The patch will not be releasing today after all, barring some sort of miracle. Remember, if Blizzard hasn't said it, it isn't guaranteed. Sorry! But heck, why don't you brush up on your patch notes anyway?