Instructions
Press the circular guide button located in the middle of your controller.
Hit the right arrow twice to navigate to the settings menu.
Select "System Settings," and then "Memory."
Choose the storage device where your progress is saved -- it will either be on your hard drive or a memory unit.
Select "Games" and navigate to and choose "Quantum of Solace."
Choose the saved game you wish to delete, then click "Delete." Your progress will now be erased.