I haven't read any of the other posts here, so I apologize if this has been said, but there is no such thing as an LED TV. It's an LCD with an LED backlight (Wikpedia it). And no TV has a contrast ratio of 1,000,000:1. There is no standard way of measuring contrast ratio, so often what producers will do is measure the brightness of the screen when it's off, then measure it at maximum brightness. What really matters is the contrast ratio of when both white and black are displayed simultaneously.
The best display technologies have blacks that are pretty much "off." Particularly plasma and OLED where the pixels are their own backllights. In those cases, black pixels are actually off.