Patch 2.4.3 is going live today. Some highlights include:

# Dispel effects will no longer attempt to remove effects that have 100% dispel resistance.
# Parry Rating, Defense Rating, and Block Rating: Low-level players will now convert these ratings into their corresponding defensive stats at the same rate as level 34 players.
# Haris Pilton has launched a new line of bags and jewelry. Check her out in the World’s End Tavern!
# Mounts at 30?! Yes, it’s true: Apprentice Riding and mounts are now available at level 30. Training costs 35 gold.
# Blood Elf flightmasters outside of Silvermoon City and Tranquillien have traded in their bats for glorious fire-breathing dragonhawks.
# Alcohol cooldowns have been rolled into Drinks: All 10-second cooldowns have been removed and replaced with the 1-second Drink cooldown.
# Numerous flying non-combat pets have had their flight height modified to no longer skim along the ground: captured firefly, dragonhawk hatchlings, moths, owls, parrots, phoenix hatchling, spirit of summer, sprite darter, and tiny sporebat.
# Nether Ray Fry (a non-combat pet) is now available from the Skyguard Quartermaster. This requires an Exalted reputation with Sha’tari Skyguard.
# Equipping an item will now cancel any spell cast currently in progress.
# Placing an item in your bank will now cancel any spell cast currently in progress if the spell was cast by that item.
# You can no longer move backwards to stop racing rams.
# When a stun wears off, the creature that was stunned will prefer the last target with the highest threat, versus the current target.

A more comprehensive listing is available Here