Picture Quality.
Matte finish on screen - can actually watch TV in daylight in room full of windows and at night with lights on - unlike Brite Screen Plasma - can watch the reflections - but not much action.
Thin enough to mount places where thicker TV's can't.
LCD 's - Edge Lit or otherwise are perfect for motor homes because of low weight, thin, low power consumption and not as susceptible to vibration as Plasma
I'm not sure buyers specifically set out to purchase a technology such as LCD or Plasma. They set out to purchase a TV and select from the offerings of various manufacturers. Many buyers are constrained by or have set a budget, certain features may be of more interest than others and last, but not least, Picture Quality, which not only includes actual color, but other attributes as well.
There will usually be a trade off or relationship between price / features / quality such that at the end of the process some will have chosen Plasma and others will have chosen LCD with some sort of lighting.