just discovered this too:  check what your default calendar is, it must be your google exchange/gmail account --that's been mentioned... but then the events you entered into your phone for a default iphone calendar of "work" or "home" will still be under those calendars.  to get them to appear on your google calendar you have to go back into those events, edit them and change which calendar they are on.  then I'm deleting those dang "work" and "home" calendars.