Telling single, strong stories is indeed an old idea, and it will be an even older idea when the TV vogue for creating viewer loyalty by tying a couple of dozen mediocre stories together into arcs has subsided again and standalone stories are still going strong.
Because sitcoms are doing so well these days
A "story of the week" was appealing when people had to turn on their TV and watch at the exact same time every week to see every episode. Most people couldn't be expected to do this, and would get lost if you changed things from one episode to the next. Therefore everything had to end as it started, so you could pick up again from zero next week, and you could air re-runs and play episodes out of order and it wouldn't disrupt continuity.
In the modern world we have Tivo, Hulu, torrents, and boxed sets. How often do you sit and watch an entire series at a go now rather than tuning in one night a week?
The medium has changed. Story telling must change with it. IMO it's for the better. I've outgrown the trite "story of the week" approach, and I think the upcoming generation of viewers has too. Even the X-Files 50/50 split between "Monster of the Week" or "Ongoing Alien cover-up" now seems like an exercise in condescension, as if the audience can't be expected to maintain an interest in the same story for more than an hour.
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...but then I don't watch TV casually. I don't leave it on in the background. If I'm going to watch it (which I do rarely), it will receive my full attention, and I understand that isn't the norm.
Generally I far prefer movies to TV. It's time out of my life either way, if I'm going to waste it absorbing non-interactive media, why wouldn't I opt for material that took more than a week to write, with substantially higher production value, filmed by a more talented director over a longer period of time, with top tier acting talent?
I make a exceptions for good sci-fi and fantasy (Game of Thrones!!!) and for current events (Daily Show)... also I watch Glee with the Mrs
