It really was significantly under a second. This was a much older model of MBP, though. A comment elsewhere in this thread suggests that maybe Apple switched fr

It really was significantly under a second. This was a much older model of MBP, though. A comment elsewhere in this thread suggests that maybe Apple switched from simply wiring the LED in with the camera to using a microcontroller for this very reason -- so the light would stay on for a minimum amount of time.