I thought it was a good movie, and definitely worth seeing, but I wasn't blown away by the whole as much as I was blown away by DDL's acting. The score (my GOD, the score), the cinematography, and the direction was all fantastic. But I think the weak part of the film was that it was really all about one character and documenting his descent (or, as someone suggested, not documenting his descent, but showing him revealing more and more of who he really is). While films based heavily upon characters are fine, you usually need more than one for them to bounce off each other, to provide arc and give the movie steam. Without that, a movie will eventually spread itself thin and cinematography and score will become ornamentation around one performance that's been going on for about two hours already.
At the end of this I was well aware I had seen something good, but not something great.
I had a great time, though. But it didn't affect me the same way other movies have. It didn't leave me stunned, and I really, really wanted to be stunned by this.