The first thing that I can say about "Inception" is that you shouldn't go to see the 11:50pm show. The film is just too long and talky for that hour. Secondly, despite what everyone says about twists and turns, you shouldn't expect a film that constantly throws you for a loop with a new angle. In short, it's a sci-fi version of "Shutter Island" with deep character replaced by complex plot constructs. If you get into complex sci-fi constructs or are interested in dream states, then this movie should keep your attention. If you are looking for character depth, twists and turns, and a film that has you second guessing yourself through the film, then watch "Shutter Island" (although that movie is hardly flawless as I'll explain after the jump.)
I just never got into "Inception". Leo's character was barely there and he was one of the most fully drawn people in the film. The lack of anyone to really root for made it hard to really buy into what was at stake. And if you thought there were a lot of monologues in "The Dark Knight", this film spends a lot more time with expository dialogue. I also felt like the fight scenes were disappointing. Nothing really stood out; there were no "Woah" moments like the semi-truck flipping over or the opening bank heist in "The Dark Knight". In the end, the movie was itself very much like a dream in that it's something that I won't really remember much of in a few days.
To read more about the film, my opinion on what the ending meant, and the further comparison to "Shutter Island", continue reading. BUT BE WARNED - IF YOU KEEP READING THERE WILL BE SPOILERS FOR SHUTTER ISLAND AND INCEPTION.
Before I get into "Shutter Island", I should explain that I think the end meant that it was all a dream. A person sitting next to one of my friends said that in a preview screening of the film, they never showed the top wobble, which would seem to be a definite answer that it was a dream. Also, there were just too many clues along the way. The impossibly thin alleyway when he was running away from the gunman (who were probably his defense mechanism projections), the comment about "taking a leap of faith", the way he saw his kids was almost the exact same image from his memory, the fact that Ellen page's character snapped out of her dream by jumping off of a building (similar to how his wife died), etc. There are still a lot of questions out there but, in the end, I think he was still trapped in his dream.
EDIT: OK, I'm back to where I was when the film first ended. I think that there was some reality (Leo on the phone with his kids) but he ended up trapped in the dream at the end. Somewhere along the line, he landed back in limbo or something. The kids seem the same age and are in the same clothes in the last scene so I just can't see it being the real world. But, then again, that thin alleyway seems like it might be in a real world environment so who knows...
After the movie ended, I couldn't help but think of "Shutter Island". Both films were both journeys into the labyrinth of the mind, ending up in a place where you can't be sure what's real and what's just been planted in your head. While Chris Nolan had the good guys planting seeds in people's brains, Martin Scorcese's "bad guys" were trying to break someone out of their brain (or were they?!) Yes, the films were different genres but they had the same core - a man's inability to deal with the loss of his wife and getting lost in his own mind because of it.
But there was one similarity that, for me, made both movies a bit of a slog to get through. Fairly early in both movies, I realized the potential ending and immediately hoped that that wouldn't be where they went. While watching Shutter Island I thought, "Man, I hope this all isn't some weird role playing experiment that they are running to get him to escape his delusions." In "Inception" (particularly the impossibly thin alleyway scene) I thought, "Man, I hope it's not all a dream." Unfortunately, both films went there and both films were weaker because of it, although for different reasons.
The main problem with "Shutter Island" was that to accept the supposed reality of the situation required one to suspend their disbelief. They gave Leo a long leash and they also didn't seem to mind too much when he basically got off of it completely. In a film in which the hero was supposed to be figuring out which reality was actually real, it seems inherently problematic when both realities seem like crazy dreams.
Christopher Nolan got around this by having most of his movie take place in dreams. When you're in dreams you can get away with some flaws (although Cillian Murphy's character not recognizing his chief business rival seemed odd. Wouldn't see Ken Watanabe's character been an immediately and overwhelming red flag?). However spending so much time in the dream state and explaining how the dream state works meant that there was little time left for actual characters. We never really knew our hero. We never really saw him interact with his family. The main case, breaking apart a global conglomerate was hardly compelling and because we didn't know much about Cobb, his motives weren't intriguing. In the end, I wanted to know whether the end was a dream, not because I wanted Cobb to get home but because I'd just spent two and a half hours staying awake and wanted an answer.
I almost feel like "Inception" is the follow-up to "Shutter Island" - it's a paradoxical staircase kind of a dream state that Leo's "Shutter Island" character might have wanted to be stuck in after he had himself lobotmized.