I'm a bit of an oddity, in that for much of my adult life, I haven't had TV. A television, to watch movies on, sure. But no TV service.
Since I've been living with my sister, though, she subscribes and I've gotten into watching several shows. The thing I find I love most is the ability for TV to create complex characters over time. People can display far more unlikable qualities but still win you over. They can be contradictory or surprising in ways that are much harder to get to in a movie.
Some of my favorites:
House - the perfect example of someone unlikable that you end up loving. Major kudos to the writers, but especially to Hugh Laurie, who can convey an iceberg worth of subtext with a single close-up, so that there doesn't ever have to be dialogue spelling out his deeper feelings.
Mary Shannon on In Plain Sight - again, in no small part due to the acting of Mary McCarthy, but also skilled writing that always places her in a situation that's designed to push and stretch her.
Also brilliant, the way she basically plays a typical man (her car, her tastes, her view of right and wrong, her difficulty having relationships, etc) and her partner is a man who displays all the typical qualities of a woman (sensitivity, nurturing, into poetry, indirect in his communication, and so on). Watch her on one or two shows, she's amusing. (In fact, the series took a season or so to find balance so that she wasn't over the top.) Over the course of the series, she's fascinating.
Criminal Minds has two great characters I love. They used to have three, but one left the show. Reed, the savant and Penelope, the hacker. In a movie Reed would not be dynamic enough to carry it, and would probably be a lesser member of an ensemble. Given a series, there's time to tease out the background of a character who is internal and socially awkward. In a movie, Penelope would probably just be a joke, the comic relief. Cut to the quirky hacker chick. But on the show, she's had time to develop into a tender and loving woman, who is, in many ways, the heart of the show.
Other characters who would be simply lost in a film, and likely would barely have a chance to breathe and develop are the secondary characters Heddy on NCIS Los Angeles and Walter in Fringe. Heddy is still a relatively minor character, but man, do I want to be her when I grow up. The hints at her exotic and exciting life, )without ever revealing too much) her cultured sensibilities, and her ability to dig in and be a bitch when needed make her a delight. And, well, it *is* Linda Hunt. Walter is wonderful because he runs the gamut from childlike and lost to brilliant and threatening. The ability to have a character who is at once endearing and terrifying is rare. I haven't seen Splice yet, but suspect that what they wanted from their creature is something akin to what Fringe captures in Walter.
Finally, my favorite character on Television: Dexter.
Need I say more?
OK, maybe you're not a fan of the series. Maybe you're one of those who think the obsession with serial killers is a sign of a sick society - but the serial killer thing is just what gets people to turn the show on. What keeps them watching is how relatable Dexter is.
We've all had times when we were confused by other people, when we didn't understand what the social norm was, or what was expected from us. When other people felt like another species, and we had to watch carefully to guess how to act (and sometimes get it wrong.) As a sociopath, Dexter has to work to pick up the social rules and cues that most of us get by default, but most of us have had times when we felt as uncertain around others as he does.
We all have a dark part of ourselves we hide, and have been in danger of it coming out. Maybe we even fear that we'll lose our loved ones if they knew about our dark secret. It's not as dark as Dexter's - but many of us have a "dark passenger" of some kind.
Many of us also have a strong internal code that guides us, and have to deal with times that our code may come into conflict with either society's laws or our own desires.
I'm definitely seeing the usefulness for TV as a storytelling medium as I learn to love these complex characters.