Have you watched any of the Red Letter Media reviews of the star trek movies? I think some of them might be longer than the films they were reviewing. A few of them have been watched a few million times. That being said, you need to be a fantastic reviewer to push into the thirty minute range.
I'd argue that you really need to be a worse reviewer to push through the thirty minute range. We really didn't say a whole lot; there's going to be a reshoot this week with the criticisms in mind to make up for it. I write overly long and I talk overly long. Its not a strength, its a weakness. There will be a time when I am a better critic and will believe in earnest that the film I just watched deserves 40 minutes of coverage. Man of Steel is not a film that deserves 40 minutes of coverage. Star Wars VII might be, but for that we'll need to see. I have my notes for improvement, and will work based off that. I might do a video review for the next one as practice, since I actually suspect that my plan to reshoot Man of Steel will go poorly. But we'll see. And yes, all of those reviews are great.
I have not. I have, however, done three series for Youtube and one for WB.com. All told, several million dollars worth of web videos. None of them were over seven minutes. It's also worth noting that their highest rated video, for ep II, is in nine parts. Part 1 has 2.6m views. Part 2 has 1.3 - click through to part II is 50%. Parts 3 through 9 have around a million views each. So it's pretty safe to say that the appetite for a 40-minute review is half the appetite of a 9 minute review, all else being equal. A 60-minute TV program, minus commercials, comes in at around 42 minutes these days. So as far as commitment, we're in the same range as, say, LOST or Breaking Bad. Can you fill up that much time? Sure. Should you? No. I saw PROMETHEUS with an IATSE camera operator, a Cinematographer's Guild cinematographer and an Illustrator's Guild storyboardist/designer. Between them they were instrumental in creating Star Trek, After Earth, Zodiac and the Chronicles of Riddick. We couldn't have found 40 minutes to say about Prometheus and of the four people there, three of them had worked with Ridley Scott and/or Damon Lindelof and/or Charlize Theron in a professional capacity.