I went to see Inception yesterday and all I will say, before thoroughly spoiling it, is that you should go see it. Now, even. Definitely a movie for the big screen.
First, a little criticism, and it is a little - it seems to me that deeper dreams are likely to be more primitive and less well-organized. So a fortress at the bottom of the psyche seems unlikely at best. I would have expected more id and a fortress like that seems a lot more superego. That one wee quibble aside, I thought it was quite the show.
As far as what is and is not a dream, which seems to be the question most people are discussing, I can make an argument that the whole thing is a dream, in the same way that I can argue that what I'm experiencing right now is a dream. However, I don't think that is what is going on in this movie. I believe that most of the movie is flashback from the initial scene in the shogun's palace, which fits well with the dream-within-a-dream story.
I'd need to see it again to be certain, but there's a break between aged Saito and when Arthur (and Mal) show up which I think represents the beginning of the flashback. Although that does make a good argument for it all being in Saito's mind. But what inception are they trying to pull off in his mind? This movie is about Cobb and, if there's a twist, it's about him.
The one thing that struck me was the very end of the movie. The kids are exactly the same as we see them when Cobb is looking in on his regrets earlier on. The light is the same, the clothes are the same, the kids don't seem to have aged at all. That scene fulfills his fantasy about what happens when it's all over. Which, to me, brings up the most interesting possibility.
What if Cobb is the inception target? What if the team is trying to convince Cobb that his wife is dead? If this is the case, I think the story failed to give any hints why Cobb would be the target, however. The dream sharing is presented as expensive and difficult and no motivation is given for Cobb to need to believe his wife is dead for someone else's profit. No hint that he was, maybe, part of some elite military hit squad or anything. So, as intriguing as it is, I don't quite buy it.
I do thing the ending is ambivalent as to whether Cobb really gets out at the end. I buy that they really were working on Fischer with Saito as their employer. But whether Cobb is still in some kind of limbo or not is not something I think I can say definitely. I can see that he might have sent Ariadne back but decided to stay himself. Maybe he thought Saito wouldn't be in any shape to clear his name and decided to live out the fantasy of living with his kids.