The entire changelog can be viewed in the previous news posting or the features section, but to make it short:
-new blood effects
-GDI Centurion AA Tank
-various new icons
-improved special abillitys for infantry
-APCs & Raider Buggys can not attack air targets anymore
-stealth detection moved from Nod Raptor Bikes to Raider Buggys and from Scrin Seeker to Gunwalker