Most people can give a pretty good cutoff for the last good season of shows like the Simpsons, its pretty easy to verify, favorite episodes all seem to come from Season 7. Nova has irritated me for a long time, its over dramatic, and has for a long time, not diagrammed a science concept with an animation. When did Nova stop being about science?
According to their page…Home | NOVA | PBS
They seem to still film some cool science’y type stuff.
All I ever get is the “History of the Mundane” NOVA programming on the TV/Cable.
Not that’s there’s anything wrong with that. 
My wife and I noticed the dumbing-down of NOVA two or three years ago.
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I haven’t watched it much recently, but looking over their list of episodes the last ones I saw that were memorable to me were the two “Absolute Zero” ones and the “Judgment Day: Intelligent Design on Trial” episode, all three from the 2007-2008 season.
I would say the last good episode was was the last one, the conclusion to Fabric of the Cosmos. I think it remains a pretty solid program except the upcoming Deadliest Volcanoes sounds a little Discovery/History/TLC ish. I’m much more dismayed over what’s happened to those three networks than any particular dumbing down of Nova. Of course, Nova is now sharing time with NovaScienceNow, (list of episodes). I thought “How Smart Are Animals” was especially interesting.
When I saw the episode of NOVA about the planet Pluto and its downgrading with Neil deGrasse-Tyson, I thought “If this is how his ‘Cosmos’ is going to be, ugh…” I agree, NOVA appears to be dumbing down its content and trying to make it more “spiffy” and “appealing.” I don’t think it’s going to work. I think it’ll turn off the die-hards and fail to attract the “Jersey Shore” crowd at the same time. It will be some middle-of-the-road bland “sciencey” show.
I thought all 4 of the “Fabric of the Cosmos” episodes were pretty good.
Same here. I hadn’t watched NOVA in several years, but those episodes drew me back in.
I don’t watch it (or anything) regularly, but whenever I catch it, I’m entertained. And my son (age 11) who adores science stuff likes it quite a bit and always learns stuff. Maybe it is a bit dumbed down, I never watched it enough to be sure, but I still think it’s a good show.
I don’t watch it much anymore. It seems whenever I have seen it in the last few years it will be some crap about a group of professors building their own catapult or sphinx or whatever. The show ends up being more about the squabbles among these professors than anything to do with science.