As announced on Samsung's Facebook page, So what? Some forums reported that :

- The device is fastest than before
- Memory space on c is decereased to 17Mb after a fresh start and hard reset (well done Samsung ! WTF !)
- Kinetic scrolling on web browser, music player, contacts, gallery but no in the menu list.

I didn't update mine yet, till read more impressions meanly because of the 17Mb space on c drive !