Sadly, the blind and others with visual impairments tend to lose some of the impact of live TV, especially entertainment. They'll get the dialogue, but they'll frequently miss the sight-based cues. Comcast thinks it can help, though. When a live performance of the musical The Wiz Live airs on NBC on December 3rd, the cable giant will include a video description track -- the first in the US for live entertainment, in fact. Those who tune in to the Wizard of Oz recreation will know when a character walks on to the stage, frowns or otherwise does something important that microphones won't pick up. While this kind of description isn't par for the course at the moment, the production is a good first step toward making it ubiquitous in the broadcasting world.