My dog doesn't care much for TV unless there are noisy birds on the screen, but other dogs I've had would sit on the couch with me and watch TV like little humans, paying closer attention to the shows on the screen than I did.
Their canine channel surfing always made me wonder how much they were actually seeing of what was happening on the screen- were they actually watching shows or just following sound and movement?
Hank Green answered this age old question on this episode of SciShow, explaining how a dog's TV watching habits may vary by breed and discussing how a dog's eyes, which are more attuned to flickering yet see less colors, see TV differently than you and me.
-Via Laughing Squid