NCSoft just announced that Aion is now going into open beta. Koreans only, sadly.
These are some videos showing of the current state of the open beta client.
Open Beta Trailer
Open Beta Cinematic Trailer
New Open Beta: Class Introduction Trailer
Assassin
Ranger
Templar
Gladiator
Sorcerer
Spiritmaster
Chanter
Cleric
Old Aion Trailer