Loads of differences, too many to mention but the main ones are:
1. GE90-115B engines, wavy fan blades
2. Longer fuselage 5 pax doors, (longer walkaround!)
3. Tail Skid
4. Boost Actuator on the MLG's, affects the rotation rate at take off
5. Main and nose gear track cameras fitted to Horizontal stab and belly with associated lights.Viewed though an extra synoptic button.
6. Bigger wing fuel tanks
7. Heavier wheels and brakes
8. Some very snazzy Crew rest areas in the upper lobes
9. hmmmmm thats all i can think of, maybe also electronic flight bag but i think that's an option