On US network tv.....
Over the last 2/3 seasons a large portion of so called "high concept" shows have failed, though i admit there have been a small few successes [Once Upon A Time springs to mind].
The list is long now, but a few of note The Event/Flash Forward/The Cape/Alcatraz/Terra Nova/Awake etc etc.
The knee jerk reaction is "stupid Americans being fed on a deit of reality crap" or "too stupid to 'get it' "....is it really that simple?, or is it the shows themselves were crap or just the usual "the ratings weren't there". Tbh i think the question is somewhat complex, it's probably a combination of many factors....not least that how people view their tv these days is radically different from a few years ago.
On demand, streamimg, media players and rips etc. have all had a huge impact on network ratings. Year-by-year viewing is trending down, but to juxtaposition this....cable viewing numbers are on the increase.
Some speculate in 5 years network tv will be over or simply full schedules of reality shows and singing competitions, as that's where the money is coming from.....sadly
lots has been said on the subject, probably raised a few times here already, but hey....tis a slow Summer/tv time