I've played one game, using the Herd list with my Lizardmen vs an Elf list.
I made some poor decisions in my deployment phase, and when my Elf opponent went first he was able to wipe out 3 of my units on his first turn. But I was able to take advantage of the terrain and hide from his archers and use my healer to keep my units battle worthy long enough to get into hand-to-hand.
The terrain rules are far better than True Line of Sight, and really make deployment and movement mean something against shooty armies.
Characters are more support units in KoW. I ran a Shaman on a Beast (Troglodon) and a Chief on a Chariot (Carnosaur) because I was used to characters being super powerful. But those points would have been better spent on Shamans on foot (so they can hide from shooting behind my lines) and more units (to soak up wounds)
The best part of KoW is that the setup/cleanup is so fast. Because you don't remove models, when the game is over you are immediately ready to play another game!
I'm excited to play another game. And I hope this catches on, because the artwork people can create with units-as-dioramas is going to be intense!