Let me get one thing straight right off the bat: I don't consider myself a big fan of Superman. That being said, Man of Steel has definitely changed my opinion of him for the better.
It's been quite a while since the last Superman movie. We definitely don't have a case of Spiderman where it seems too soon, which definitely helps the likability of the film (not that I didn't like Amazing Spiderman). We have Zack Snyder at the helm, whose directed two comic book winners in 300 and Watchmen, and a couple stinkers elsewhere. He does a fine job with what he's got, and doesn't use any of his not so much trademark as dreaded slow motion. David Goyer's script could have been better, but it's not too shabby. I'll get to that in a minute.
Easily the greatest thing about this movie in Henry Cavill's performance as Clark Kent/Kal-El/Superman (Man, what do we call this guy?). He brings a lot of depth and humility to a role that I previously thought to be shallow and boring. It is impossible not to like him while watching the film. Complete and utter props to doing what I thought impossible.
However, I thought a lot of the other characters, save for Russel Crowe who was actually quite awesome, were really underdeveloped and/or under-utilized. Lois Lane in particular was a bit annoying in parts of the film. I mean, it's the twenty first century, can we please stop throwing Lois into the air and having Supes catch her? Can't she have some weight? Amy Adams does an admirable job with what the script makes of her character, but it's obvious the Lois is lacking. And Michael Shannon's General Zod is lackluster at worst and mildly scary at best. I couldn't take him extremely seriously as the villain, which is not terrible because it's often his henchmen we're left to deal with. Christopher Melloni also has a small role, in which he does well. You remember him anyway.
The story is also mildly problematic, but has some really great moments. It is your origin story, which is getting a tad tiresome after so many origin super hero stories in the last few years, but it's different enough from the ones previously brought to screen that it is exusable. The first half of the movie is largely a character piece, getting to know how Clark Kent gets to where he is now, mostly told using flashbacks. The second is what you were probably expecting, lots of action packed fight sequences and an overabundance of pyro. Now, as you guys know, I don't mind a bit of some good 'ole fashioned explosives. But at least half an hour of the big bang could have been cut from the film with no harm done. Metropolis is reduced to nothingness and it's not even sequel time yet (although one is already in the works I'm sure). But I loved seeing Clark's relationship with his human parents, and the the oft-reality based struggles he had to deal with growing up. It lends more depth to the character.
The film also focuses on a lot of the more sci-fi elements. I was expecting more Clark Kent than Kal-El, but got the reverse instead, which is not a bad thing, but I'd like to see more humanization in the sequel, which I know sounds weird in terms of Superman. But that's part of my problem with why I never liked Supes before: He never seemed human. Man of Steel does an amazing job of giving more depth to the character, but I still wanted more. This is definitely one of the times where I'm hoping the sequel delves into a lot more.
Despite a lot of problems, Man of Steel does an excellent job of revitalizing Superman in the same way that Christopher Nolan revitalized Batman, but with different characteristics. Whereas Nolan emphasized Batman's angst and vicious thirst for justice, Snyder emphasizes Superman's honesty and willingness to protect the people of Earth simply for the sake of good, while still starting on the path to humanizing the character. Don't miss it if you like super hero movies and can handle a solid hour of stuff exploding.