Flash memory is ever more on the advance. Only this week presented Samsung first really available hybrid non removable disks, which have beside the actual memory still an additional Flash memory, which is to accelerate a working under Windows. Apple continues even still another piece: In the second yearly half the enterprise a Notebook wants to present, which has no more conventional non removable disk, but only over Flash memory.
This brings several advantages in a Notebook directly. In addition thus the memory less river needs, than a normal non removable disk and is clearly less susceptibly in relation to external influences, as for example vibrations.