I thought it was a great film. I think people misunderstand the ending.
The way I always interpreted is that the director doesn't want you to speculate over Di Caprio's reality, but question your own. He's basically implying that you can never know yourself whether you're existing in a dream world or not.
Whether Di Caprio is dreaming is of little importance as he clearly believes at the end of the film that he isn't, so to him that's his reality.
People speculating over the totem wobbling and things like that are, to me at least, missing the point.
Overall, I think it's far better than most of the tripe that comes out of Hollywood these days. I'd happily watch it again.