My thoughts so far: it looks good. It has a flavour of the older editions rather than 4E, but still seems like a progression from that system.
I’ll still have to wait and see how it looks come 2014 when the full rules arrive, but I’ve already got some ideas churning.
I had an old D&D 3.5 campaign that followed some colonists crossing an ocean. I may adapt it and see how the new rules work in that setting.
Of course, that setting involved an entirely human society encountering demihumans for the first time in several centuries.
The core concept of a recent rebellion against a council of liches is still sound. I’ll just see how people take to it. There’s obviously a tendency for people to be a bit blasé about darker magic, but at the same time still have very little trust in people that can use it.