In University I did not have a TV in my room (like I had money for cable!), but I do remember watching a lot of movies and staying up late playing computer games. However, I often had later classes in the morning so it usually wasn't detrimental.
Living on my own, I take a pretty strict stance on my sleeping routines. There is NO television in my bedroom now! Well, technically....I am in a studio so there is a TV in the same room, but I never watch it from bed. I also never use my computer in bed (I read before bed off my Ipad, but I don't browse the web, check FB, or twitter). Sometimes my phone ends up in bed with me, but I often text whoever I am chatting with that I am going to bed and goodnight!
And you know what? I have been sleeping amazingly these past few years. I think designating my bed as a "sleeping zone" helps my brain get ready to shut down. I have my nightly routine and 9 nights out of 10 I just drop right off into sleep within 10 minutes of hitting the pillow.
Do you have a TV in the bedroom? Do you like ir?