This is apparently a coming soon title. Even though its an MMORPG it looks extremely hack and slash and may be rather accessible. A google translated korean blog I've found indicates that it will be using the source engine. I don't see a specific day for release, but I am seeing 2009 mentioned in the same breath as a lot of stories about this game, so I think we can expect it this year. This game is hosted on Nexon which is a game portal. I'll be chatting about it soon. Below is another trailer with some different views.
Update:Apparently closed beta ran past december, so chances are this is not that far off from being released. It could be available as early as a couple of months from now.