While these are marked in one of the group player's handbook, I thought it would be nice to have a compiled list somewhere for a quick reference while drawing up characters.
New Talents
New Proficiencies and Skills
New Weapons and Weapon Deviations
Shields and the Wielder's Size
A&8s Secondary Effects
Called Shots Secondary Effects
Attacks and Damage
Near Perfect Attacks
Reach and Closed Spaces
Revised Shield Bashes
NPA/NPD and Unarmed Strikes
Thrown Weapon Damage
New Combat Manuever: Power Attack
New Combat Manuever: Strike the Weapon
Module Armor Pieces
Lithic and Obsidian Weapons
Better Barbarians
Flails ignore Shields