I’ve a sneaking suspicion that the processing overhead for handling this sort of thing – particularly with high-def footage – is ‘non-trivial.’ Which is to say: cripplingly hard. See also these previous stories, ditto.
Dual-processor laptops are one thing; eight-way desktops with hyperthreading, matched with stream-processing video cards, all coordinated via OpenCL implemented at the system level: well, that’s going to be something else when it comes to heavy-duty video processing.
Personally, I find it more than a little scary. We’re barely used to still photographs being routinely and heavily manipulated; processed video is something we expect of Hollywood, but not home movies. I suspect we’ll adjust less quickly, culturally, than the technology will propagate.