I played the MapleStory 2 CBT a few weeks ago and I admit it was very fun to play, I have a few screenshots to share.
As you can see it's a 3D Top Down MMORPG of sorts, it has pretty quick leveling and you can pretty much reach level 50 in under a week. Level 50 is the level cap.
The game revolves around mostly dungeon raiding and bossing, and to level you do quests. The most I can say is that It's a fun little game and I enjoyed it when the CBT was occuring, Hopefully an OBT comes soon or better yet the full game!