Holy crap. First off, massive buffs to flying MC's, and some nice tweaks to MC's in general. Bloodthirsters and winged DP's are looking much more attractive now.
HQ's can be scoring, if you choose the right attribute. Last turn objective grab with a Chariot? yes please!
ALLIES are almost certainly for a main army and a detachment in the same army! I can't wait to see what's in the new CSM codex!
Now... it worries me that they state MC's are AP2... is that implying power weapons are AP3? Worried...
Psychic disciplines, don't know how much effect they'll have until the book is in hand.
Buyable terrain... awesome. I'll take an autocannon or whatever, thankyouverymuch.
Models removed from the front... honestly, I kind of like this. I don't like the hassle of wound allocation now, and people standing there going "yeah... hang on... I'm thinking...." because every single one of their stupid paladins is too special to die.
One of them took a Bolt of Tzeentch to the face! WHICH ONE DIED?
Assault range is 2d6. Alright... liking this, actually. You won't roll under a 6 most of the time, I am totally fine with this.
Hull points. This, along with the vehicle nerfs, does exactly what was needed to be done to vehicles- make light ones weaker, and heavier ones stronger.
Overwatch :D Flamers jump in, burn, overwatch, burn again! Not sure that's exactly how it works, but if it sacrifices shooting that phase for instant shooting later, it still might be a good option for a lot of units.