I've been damn impressed with Five Nations so far - I like that it went to route of mostly fluff, and it gives a ton of stuff to work with.
I have to also say it is nice to have civil conversations about it here - over on the Wizards Eberron boards, there's an extended rant-fest over how a single paragraph in the Aundaire section ruins the entire spirit of the setting for a number of people, and they wish the authors woudl just listen to them, because they must be right.
So, good show for being civil, ENWorld.