I do a lot of writing with the telly on. I'll pause it if I'm really busting stuff out, but it doesn't "keep me from writing." Of course, I'm usually running something like a documentary that somehow applies to the WiP.
When I don't feel like writing, sick, tired, general meh... I'll watch heaps of stuff. With my laptop on, and the WiP open. Often as not, I'll start typing during a commercial... and keep going.
In any case, I've found myself incapable of watching anything without examining the storytelling on the screen. Playing "Oh, I see what you did there, Mr. Whedon. You magnificent bastard, you." Studying what works for me in a show, and figuring out why a scene resonated with me. And looking for mistakes NOT to make. "Oh, that was just tooooo convenient... cheap and lazy writing... you should have given the knife to the monkey...."