Besides the canon warping the movies is amazing. I enjoyed it a lot more then I had Thor. To note though if you go to the movie expecting action because of the previews with things like Magneto lifting a submarine out of the water you will be disappointed. That is at the end of the movie though it is somewhat to be expected as its an origin story type movie.
Now if you want character growth and a brilliant story its quite amazing what they have done with it. While as mentioned they did change the canon quite a bit the story they replaced it with was top quality. Quite amazing what they have done with it.
A good movie and you should see it if you like stuff like it and don't mind that they changed the story. The only thing I feel sad about is that they had to compress all of the origin into one movie. A good number of parts would have been fun to see as movies if expanded upon.