TQ has released Combat Videos about the Assassin already. For those who have any interests in this new class, you can watch how the assassins' AoE skills work in PvE and in group combat, such as Guild War. And from the videos, you can also see how the Oriental Assassin combating with other classes too. Some of the skills do look cool, especially the XP skill.
Read more details and see all the videos from their official website:
http://co.91.com/news/2013-01-25/Oriental_Assassin_Preview_Combat_Videos.shtml