TERA is under development by Blue Hole Studios, a South Korean MMORPG developer founded by former members of NCSoft. I know what you're thinking: "Another Korean grind-fest." Well, watch that trailer and think again.
As you can see (be sure to check out the other TERA trailers here, too) the game is heavily action-focused, with defense and evasion forming the crux of combat. Not only that, but the publisher, En Masse Entertainment, is heavily involved with the community, meaning the finished product will almost certainly be in-touch with what MMO fans want and expect of a next-gen MMORPG.