I don't know if I can describe it any better than that. A conventional critical analysis of the film would be tricky. It's immaculately constructed. Other than some over-long, disorienting chase scenes and some clunky dialogue here and there, it borders on technical flawlessness.
I don't want to pose this as a criticism because I don't mean it as such, but it is a curiously humorless and emotionless film except for the very palpable longing Dom (Leonardo DiCaprio) feels for his family, represented beautifully by the motif of his children's backs. Inception presents the viewer with this powerful emotion, but for the most part does not allow us to experience it. We are held at arm's length, observers in the layers of dreams the characters traverse.
I guess this aspect of the film surprised me because one expects any movie about dreams to be immersive and subjective. Inception is most definitely experienced objectively. Rather than being immersed in the action, we are reminded of all the steps that must be taken to complete the process. Something at the complete other end of the spectrum but the same genre (roughly) would be Ocean's Eleven, where the viewer knows almost nothing about how the heist will happen and is swept up when it does. In Inception, the viewer is watching from the perspective of the mastermind, aware of every step.
Again, all of this is largely observation, not criticism. I thought the film was a masterwork. It's incredibly original. It's like nothing I've ever seen, and that's certainly saying something.
Highlights were Joseph Gordon-Levitt and Tom Hardy, who added really the only wryness and humor in the entire film. Ken Watanabe also got to be pretty fun. Gordon-Levitt's anti-gravity fight scenes were amazing. Cillian Murphy did an admirable job considering he wasn't given much to work with. DiCaprio, although very restrained, communicated Dom's tragedy perfectly.
I'm going to see it again tomorrow, so I may amend this entry if I have any other insights, but I felt I had to get out my thoughts right after the first viewing.
So, what did you think of Inception?

I FUCKING LOVED IT
I thought it was great, and I'd agree with all of your observations. I remember being completely sucked in to The Dark Knight and was surprised that this movie was doing everything in its power to keep me out. I was really WATCHING this movie, I was not immersed in it. Sort of how you observe a beautiful painting at a gallery.
I think part of that feeling might be intentional, to keep the veneer of unreality over everything. I was reminded of how strange and mechanical most of Mulholland Drive is, and how that was used in the story.
Inception does have the distinction of being one of the few films I've seen where visuals were not only there to dazzle, but really informed the story as well. I feel like I learned more about the world, and the characters, by what I saw on screen.
There was a bit of a nagging sense of it being over-wrought, though. I've been told that Nolan worked on the script for ten years, and I did get the feeling that I was watching somebody else's precious object. Thankfully, this passed quickly.
All that said, I loved it.