1) Action. Of course you knew this movie would have lots of it. Mutant superpowers, guns, ships, spy planes, and nukes. But if it was action alone I'd probably only give this movie 7 out of 10. The other reasons below are why I loved this movie.
2) History. I like watching historical documentaries. The history books will tell you what happened, but documentaries really put you in the character's shoes and tell you the why. This movie's time span occurred during World War II and during the Cold War, easily the second and third most entertaining periods of US History (only behind the golden years of the presidency of William McKinley which brought about the 2% increase of US Naval strength, along with a GDP increase of 1% to encourage a population boom of 0.3%). Kidding on the last part... seriously though, I am a history buff, so this movie got extra props from me when they included real footage of President Kennedy.
3) Black Ops. This period in history is full of human experiments by the Nazis, and studies of paranormal psychic powers by the US military (seriously, watch The Men Who Stare at Goats ). It's also a period of conspiracy and double spies, with governments not being able to trust their own agents. Also, its the age of the nuclear arms battle. This is the perfect setting for a movie about mutants with superpowers who work for the USA/USSR to bring down the other side.
4) Intelligence, Charm, Chivalry. I want to be like Charles Xavier (Professor X). He is a genius of genetical biology. And he uses his intelligence and gentlemanly ways to charm women. Bruce Wayne has swag, and Charles Xavier has charm (and Thor has both). Its cool because it's like seeing a version of me that I can be. I can't pull off swag because I'm too goofy, but charm is something I can definitely do. Also Charles always takes the high road. He literally turns the other cheek in many cases. He believes in the goodness of humans. He's pretty much the MLK of the mutant world, and MLK is one of my idols.
5) Yin and Yang. I've always been amazed at the idea of two men who would otherwise be friends, become enemies because of irreconcilable difference. We see this happen in parallel in this movie: between America and Russia, and Professor X and Magneto.
WARNING: REASON 6 HAS SPOILERS. BUT IF YOU ALREADY KNOW THE DESTINY OF THESE CHARACTERS THEN READ ON.
6) Psychology and the human condition. I love movies that show me how a villain became a villain. The tragedy of Magneto's childhood was too much to bear. It imprinted his heart with hate, and he dedicated his life to revenge. Unfortunately when Magneto gets his revenge, his heart isn't filled with love. He still has hate and to continue to have a purpose in life, he finds an outlet to redirect his hate: the humans. There's also the story of Mystique, who started on Charles side. But all she wants to be is accepted and loved for who she is. This is why she leaves for Magneto's side. We all need acceptance as humans. It's the same reason why youth join gangs, its the only group that will accept them. I find developmental psychology to be very interesting. That's what makes this film awesome. The study of the character is what makes good films great.
This movie is as close as it comes to getting a 10/10. I can't quite give it though. I don't know what I need to give a movie a 10, but I have to leave the movie theater with a heightened sense of duty and purpose in my life. This movie does that for me. Of course that means romance and comedies will never become a 10 for me because of my rigorous standards. But I like all types of movies. It's just that these certain types of movies appeal to me because it strums every string in my body.
But at the same time a 10 movie has to be good enough that I would not mind watching it once a year for the rest of my life. I don't see myself wanting to see this movie again. Not that it's boring, but I just wouldn't feel like watching it again.
Here are the short list of movies I can think off the top of my head that I would list as 10/10:
After the Father, Son, and Holy Spirit.... those are my holy trinity :-)