In New York magazine, Adam Sternbergh's piece about the decline of Lost captures my sentiments exactly. The show is getting worse and worse because the creators are forbidden from ever solving the central mystery in order to keep it running for as many seasons as possible. So when some smaller mystery does get explained, it never helps explain what's really going on.
There is, however, a simple solution: Change the format, or at least reimagine it. When it so-called arc shows, we need something between a mini-series and an open-ended run. We need the TV equivalent of a novella: the limited-run show. Series driven by a central mystery (Twin Peaks, The X-Files) peter out precisely because they have indefinite life spans. The writers are forced to serve up red herrings until the shows choke on their own plot twists. (Whereas 24 works because it's more cliff-hanger than puzzle—though Jack Bauer is surely the unluckiest man alive.)
