Thanks for mentioning the digital optical track on film. I wasn't aware of
that. Don't forget, though, that video has its own version of digital audio
called PCM or pulse code modulation, that is available in _consumer_ Hi8MM
format from Sony.
As far as video being as big as theatre images, it's already happened with
HDTV. These are _big_ screens, with an aspect ratio equivalent to 35MM. The
reason why we haven't seen more of these, and I think it's a sound one, is an
issue of compatibility. HDTV's signal is completely incompatible with the
NTSC standard, although they're working on a compromise system that would make
it compatible. With any format, film included, there are social and economic
conditions that dictate the so-called quality of the image.
You should check out some of the literature written on HDTV if you're
determined that video is an inferior format to watch than film. Many Japanese
production firms have already started using it. You may even be able to get a
hold of an NTSC dub of something shot in HDTV.