So I saw this last night, I'm a bit groggy up a 9am after getting home from the movie at 3 so I hope my review makes sense. Overall, I thought the movie was very good. Unfortunately, I think people, including myself, are going to compare this to the Batman trilogy, and it's just not at that level. If I were to give it a grade, I would probably give it solid B. I also think it's the best of the Superman movies, so take it for what its worth.
My biggest issue with the movie is the same issue I have for all of Snyder's movies. It's like whatever direction or style he wants to use for his movies, he takes that direction to the absolute extreme. It's like he wanted to out Christopher Nolan in making a Christopher Nolan movie. With his other movies, he wanted 300 to become a comic book come to life and he made it to the point where it became somewhat cartoonish. In Watchmen, he took the graphic novel frame by frame and transported it into the film. The movie seemed overly long and boring in parts trying to cram so much into the movie.
I can see where the critics are going with the movie being to serious. Its like he wanted to make the most serious, intense comic book movie ever made that by the time the movie is over I almost felt deflated. I read a review that used the word "shell shocked" and that's exactly what it was like. My wife liked it more than I did and she compared it to TDKR, which was her favorite and my least favorite of the batman movies. We came to the conclusion that if you think TDKR is superior to TDK, Man of Steel may be a better movie. The movie didn't really seem long, the action was great, and I'm not sure what critics are saying about thin plot. I also saw it with a friend that loves Superman and he was disappointed by some of the things they got wrong. I don't really remember what he said, something to do with the lizards, but I don't read Superman, so comic book nerds beware. But he also loved the movie.
Overall, it was a good movie. It's better than what I'm reading from the critics, but it doesn't quite measure up to the hype that was generated from initial screening. I don't think it will end up being the movie of the summer. From an enjoyment factor, I did think Star Trek was better, but it's hard to compare those 2 movies.