It pwns WoW's face. I've played both and would rather play AoC then wow. WoW is entirely gear based and the only real PvP you can do is in a battle ground.
Age of Conan lacks end game content at the moment. There are a few raids/dungeons but its not like a grind like WoW. The whole game has storylines and are not aimless quests for better gear.
Guilds can build guild cities, and each player can do every gathering profession. Gather stone, metals, wood, etc. As well as 2 main professions, Alch, Architect, etc. Unlike WoW where you pick 2 things and thats it.
Age of conan's combat system just makes WoW look silly, especially if you really want to play the game. Each swing is a stroke on the keyboard. Your person does not attack unless you tell it to attack and you control each swing of your blade. You can also block, unlike wow's automatic combat system. Set it and forget it! Auto attack!
Its just a more mature, well thought out game. Takes a beast of a PC to play really but its really a good game. Leveling in Conan is so much more fun the WoW.