1) The graphics are just...incredible. I never got tired of just staring at the surroundings and the armor is amazing.
2) Being a healer and not just staring at colored blocks the entire time was a refreshing change. Also being able to nuke and heal without changing specs was awesome ^_^
3) There was enough different from WoW to keep me interested, but same enough to not throw me for a complete loop
4) Quests are no more grindy than WoW, which was surprising considering this is a Korean MMO.
All in all, a fantastic getaway until MOP rolls around, and perhaps even after that!