Before you go into the theaters or waiting for home media to be released, you have to know this, you can't compare this to the old Superman franchise. It is so different from the old ones that a lot of people didn't like the change. For me, personally, Man of Steel is a good Superman movie in its own right.
If you're craving for a more action movie route, Man of Steel is definitely the movie for you. Right from the first moment the movie started, you're introduced to the fiery & crumbling world of Krypton, the birth planet of Superman. Jor-El (Russell Crowe) is directly placed into the fight with General Zod (Michael Shannon), the main villain of the movie. As far as the action sequences go, Zack Snyder nailed it, it was brilliant! But at the same time I feel that some of the action sequences have dragged far too long, a bit unnecessary to be honest.
After the opening, the movie slows down a bit. It is time to explain the theme of the movie. Since this is the reboot of the franchise, origin story is inevitable, but executed in a different way. I think the use of flashbacks to tell the origins of Superman (Henry Cavill) is a smart move, with him finding himself who he really is, then think of his past is really good. Not to mention great cast and performances by Amy Adams (Lois Lane), Laurence Fishburne (Perry White), Kevin Costner (Jonathan Kent) and Michael Shannon (General Zod). Henry Cavill plays the role of Superman well, but sometimes he might played the role too seriously.
In general, Man of Steel is finally a Superman film that we all need and want to see. Despite the overblown and over long action sequences, they were brilliant done. The good performances by some of the cast and a different take on Superman is a great plus to the movie. I think it deserves a sequel.