I was pleasantly surprised to see mention of my review for Knowing at Cinefantastique Online. Steve Biodrowski, in citing my review, brings up a good point about my apparent contradiction calling Knowing a popcorn movie on the one hand, while raving about it on the other. So here is my short explanation.
The term popcorn movie has been used, mostly and usually, as a disparaging term for films that pander to a mass audience (and even smaller ones) while showing little or no creative or artistic effort, design, or thought. I understand this, but I choose to not use the term in this way.
Quite frankly, and sadly, a sizable amount of theater and straight to DVD movies, both horror and non-horror, can be categorized as popcorn movies if the term is used in this way, forcing it to lose the value, the sting of negativity, if you will, it was originally meant to convey. There is now an expectation of mediocrity in film production greater than the expectation of excellence; this renders the negative connotation, usually applied to the use of the term popcorn movie, superfluous.
I rather avoid this and use popcorn movie to mean a film worth seeing--whether it appeals to a mass audience or not--that is enjoyable on possibly many levels, including the emotional, psychological, and spiritual states one may experience while watching it, and being thought provoking as well. The film may be disturbing, enlightening, or just plain fun, but the bottom line is that you, the viewer, are left with a sense of "damn, that was good." Using this, admittedly personal criteria, I consider Casablanca (my favorite film by the way), Citizen Kane, and Halloween popcorn movies, along with many others I have enjoyed watching, like Watchmen.
I was left with a sense of damn, that was good after seeing Knowing. I hope you experience the same.