Obviously most TV sucks, as do most movies, but for whatever reason movies have long been respected as art while TV has long been rejected a lesser medium.
I like TV more than movies, especially now that we have nice HD wide screen teevees, because I'm not a big fan of short stories. Movies are basically short stories. (Any novel has to be cut to shreds to be turned into a film). They have a beginning, a middle, and end, and it all has to play out over about 2 hoursish. TV has the capability of showing longer stories, of genuinely being long form literature. Not that it is usually great art, of course, but it actually has the greater promise of being so.