From what I understand there is an auto-targeting system (presumably the closest opponent in front of your character), and you left click (by default) to attack. You can try to dodge magical attacks or arrows if you are far enough away to have enough reaction time, but the combat is not a micro-managed attack / dodge / block type system.
The change in control system was predominantly to be able to handle human movement / combat and dragon flight / combat effectively and in a similar a manner as possible (so people would not have to switch controls when changing form). Mouse clicking to move doesn't work very well for flight, though it can be ok if the camera angle is kept fairly high, and there are additional controls used to change height (with an over the shoulder view, you may not be able to see where you would need to click to move to a particular location, etc).
