I submit that it is not.
Famously, Roger Ebert appears to be the only major critic who not only praised Alex Proyas's film, but vigorously defended it. Having now seen the film for myself, I'm tempted to say that Ebert went a little far, but who cares? Knowing got slammed by pretty much everybody else, critics and public alike, though beyond a certain sappiness in the last chunk (said sappiness stemming from an implication of what will happen some years after the film has ended that is hard to not be a little put off by -- see the film and you'll know what I'm talking about) I cannot figure out what in the world is supposedly so bad about it.
The story is thrilling and mysterious, and kicks off in a very intriguing manner: fifty years ago, a young girl puts a piece of paper, on which she has written a series of numbers, into her class's time capsule, which is unearthed during the present day by a new class, and the student who ends up with the numbers is the son of a widowed atrophysics professor played by Nicolas Cage. Certain mind-boggling coincidences lead Cage to believe the numbers predict major disasters, culminating, he comes to believe, in the end of the world.
This is a science fiction disaster film, like The Day After Tomorrow and Independence Day, but it's distinguished from those two by not sucking, and by having a brain in its head and sense of conviction about its themes, among them being religious faith and the nature of the universe. It's an Apocalypse film that realizes that the Apocalypse -- religious or man-made or plain old shit luck -- is kind of a big deal.
Is that the problem so many people have with Knowing? That it's sincere? I'm inclined to think so. That's not to say that there is no room for legitimate criticism to be directed towards the film, but Ebert seems to have been the only guy to engage with the film seriously. Every other reference to the film I've seen has been casually brutal and dismissive. But Knowing, like Deep Impact, is genuinely interested in the implications of its story, and the Irwin Allens and Roland Emmerichs and Michael Bays are not. I honestly feel like that puts some people off. Also like Deep Impact, Knowing takes its disasters seriously, and doesn't treat them as eye candy, or even as things that can be stopped. Both films also attempt to deal with the grief and horror that follow. Popcorn films aren't supposed to make you feel bad.
I suggest that anyone who hasn't read Ebert's review, or his blog post, on this film do so. I'm not convinced that Proyas was as successful with this film as Ebert says, but Ebert has without question dug out what Proyas's intentions were, and nobody else seemed to care to do so. More importantly, though, give Knowing a chance. I don't claim that this is a great film, and I don't believe that every single person reading this is going to even like it that much. But I happen to think it's pretty good, and that it deserves a shot. Knowing is trying something.