I keep on seeing people say that the ending is so crazy and shocking. I think Ryan Davis said it in his review too.
But what was it that was so mind blowing?
Was it the last level where you rewind and see the princess running from you, or was it something in the books at the end? Because those books at the end made absolutely nothing clear at all for me, and that's frustrating.

Go check out some of the ending discussion threads if you want impressions, although, if it didn't do anything for you, I doubt it will upon reading any of our theories about it.