Here's a trailer:
WARNING: Spoilers ahead.
I found it to be a combination of some opposed styles, combining on one side the exploration of the mind through dreams and symbols with Matrix-style effects and Mission Impossible-style action.
While it's a good combination of styles, none of them prevailed, and each style was sacrificed somewhat in favor of the others. As such you have a movie that could have been a great effects-movie (but it's a bit too convoluted for that), a great action movie (but it's a bit too convoluted for that also) and a great psychological movie (but it's too action-packed for that).
Also, the trailer makes you think the movie is about the power of an idea. It's not (well ... it is about that, to the degree that say ... Ronin was about the power of a suitcase - that is to say, not at all).
I liked a few themes in it (the "going deeper" in the subconscious by entering a dream within a dream for example). Maybe I found it interesting because it sounds like a plausible hypnosis technique (I'm not sure).
I also liked the symbols (though some were repetitive and simplistic), the ending, some of the dialogues and I especially liked the idea put-forward at the end:
Mal (a figure within Cobb's subconscious) tells Cobb that maybe his reality is the dream because it's implausible for nameless corporations to chase you all over the globe - it sounds too much like a dream.This idea, striking to Cobb at the time, seems to support one of the possible interpretations of the ending of the movie.
I also found the idea that at the deepest subconscious level there's a common ground very ... attractive. It gives you something to think about (if nothing else).
What I didn't like about the movie was ... well for one, I would have expected Cobb to actually be an expert in the mind (considering the movie starts by portraying him as such). Instead, he appeared more like an action man who "knows all the tricks".
Cobb: I know how to find secrets from your Mind, I know all the tricks!(see? :-D)
First, there's not much about those tricks in the movie. There's the Totem idea (actually that was quite good), the idea of things being hidden in symbols of safety (a safe within a house within a house and a safe within a wall and a safe within a fortified fortress? I mean ... subtle much?). Then you just have some veiled references and explanations in conversations that didn't touch on much of anything (some explanations on how the mind builds the dreamscape, why you shouldn't change somebody else's dreamscape endlessly and so on).
Through the movie, Ariadne - a beginner in the field trained by him - trumps him over and over again; and ... err ... Ariadne constructs mazes. It must have been a coincidence.
In this light, it seemed like, while Cobb knew all the tricks, he was not so much of an expert on "all things mind". He also ignored the problems in his own mind to such a blatant degree that he risked ruining mission after mission (the first mission is complicated by his issues, the second even more so, and we're left to understand this had been going on for a while), while the most important thing in his real-life (living with his kids) was at stake. I understand having a troubled past and living with your own demons, but this looks a bit like a plot-hole, or like dilettantism on Cobb's side.
Second, the mind-scape issue is also lacking a bit and incomplete. I found a much better exploration of the subconscious and symbols the mind creates in What Dreams May Come for example.
While the movie abounds in dream-specific symbols and items (a spinner that goes on and on in a dream, the coherence of reality being broken, heavy rain because the dreamer had to go to the bathroom, or walls that squeeze you while you struggle to get through) any dream-like feeling is completely missing. There are other movies that manage it way better (see the tensioned atmosphere in Lester Burnham's dream in American Beauty, or Mary Lomax' dream in The Devil's Advocate). Such an atmosphere would have probably detracted from the intense action though, so it was probably sacrificed (if it was even considered).
Third, there was the whole "going deeper in the subconscious than anyone else in the whole world, and synchronizing three things falling at the same time and at different speeds, and in three different dream levels, by three different people with Robert break into his own mind to construct a false idea in a way his own subconscious will not reject" thingy. Did I mention convoluted? I thought I did.
I had two friends ask me "Did you understand anything?" the moment we met outside the cinema. I understand the question is being asked by others who saw the movie also.
All in all it was an entertaining movie for me. If you want an action movie (that's not about the power of an idea - as the trailer suggests) but more about Mission Impossible-style action using Matrix-style effects in convoluted overlaid dream-scapes, go and see it.
It was entertaining.