Combat is more fluid and seems to have more depth.
Uses a combo system where your skills can completely change based on the sequence of use.
It also has a pokemon-ish element to it. The world is full of dragons, right now I think there's about 300 different ones. These can all be tamed. Once tamed they function somewhat like a WoW hunter pet, but they are also your mount. You can train your dragons, you can have your dragons train each other to get different skill sets, that kind of stuff.
There are also sky island instances where you can build a house(in a modular fashion). Each sky island is governed from a castle, whoever owns the castle can set taxes for the entire island and lots of other fun stuff to either be a benevolent king or horrible tyrant

. Guild
PVP involves sieging and taking these castles.