i may be crazy on this, but today I noticed that when typing, with key vibrate enabled, the vibration was very weak. Vibration duration was set to 102 in advanced keyboard settings. When I got home, I plugged the phone into the charger, and shortly thereafter, answered a text. The key vibration was much stronger. I'm wondering if ICS throttles back vibration intensity as the battery reserve lowers? If so, this may explain why many are complaining about weak vibrate on incoming calls....although I think that even when plugged in to the charger, the SGN has a weak vibrator, compared to some of the other Android phones available.