I saw it at the IMAX last night. I was thinking the only recent movies that get me to pay the admission are by Pixar and Nolan, but then soon as the previews started rolling, I remembered Avatar (it was so nice not to have any previews with that one).
I thought this movie was sort of like Memento, but with a budget on steroids. My friends likened it to Eternal Sunshine of the Spotless Mind, and Being John Malkovich.
My dreams were more vivid than usual last night!
The suspension of disbelief was a little more challenging than usual to me, because there were just a number of little things that "just can't make sense". With something like Avatar, big blue people that connect to nature may be a stretch, at least that was the only big stretch I think I had to make there.
The special effects were pretty cool, I think the best being in the hotel.
Honestly though, I would have been happy to save the $18.50, and just wait for it on BD. The PQ is good, immersive, but my system still has better black detail, I think. For full disclosure, my opinions on movies often seem to be the opposite of what the masses say, and I think it has to do with expectations.
It was entertaining. Trippy. Interesting. Worthwhile watch, but IMO, not a can't miss at the IMAX. At this same theater the digital/dlp is still $16, but if you can find one of those for much cheaper, perhaps as a matinee, that's what I would say. Enjoy.
Edit: I disagree that this movie is superior to Godfather II.