The same question (but no answer) is here , and several other reports can be found on other sites (for example, here )
Not perfect, but targeting 3.1 seems to solve the problem.
MPMoviePlayerController scalingMode - MPMovieScalingModeAspectFit (, MPMovieScalingModeNone , ) play, MPMoviePlayerScalingModeDidChangeNotification > . , ( !), . , , , . , ?