What does HTML5 have anything to do with it? Many times you get linked straight to a movie file and the browser is expected to either play the file or download

What does HTML5 have anything to do with it? Many times you get linked straight to a movie file and the browser is expected to either play the file or download it (based on mime-types). If they are disabling the Quicktime plugin on OS X, then at least just download the movie file even if the mime type is "video/quicktime". The error screen they are showing now is scary enough that most people will abort out of it.