A couple of notes.
First, IMPERIAL KNIGHTS have DOUBLED their movement! (12" in movement phase, double highest die in difficult terrain) Ouch! This has also been added to the core rulebook and Escalation for all Super-Heavy Walkers.
CHAOS DAEMONS - Blood Thrones and Skull Cannons have gained Bloodletter Crew, with additional combat attacks, etc.
SPACE WOLVES - Murder Claws now +1 Strength.
TAU - Marker Lights, when used to ignore cover, are clarified to only work on the target unit, not on any other unit a Blast scatters onto.
Thats more or less it. Quite underwhelming except for the Super-Heavy Walker boost! Revenants anyone?